Abstract
We will denote by d(n) the number of positive divisors of n, by σ(n) the sum of those divisors, and by σk(n) the sum of their kth powers, so that σ 0(n) = d(n) and σ l(n) = σ(n). We use s(n) for the sum of the aliquot parts of n, i.e., the positive divisors of n other than n itself, so that s(n) = σ(n) - n. The number of distinct prime factors of n will be denoted by ω(n) and the total number, counting repetitions, by Ω(n).
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Literatur
Jennifer T. Betcher and John H. Jaroma, An extension of the results of Servais and Cramer on odd perfect and odd multiply perfect numbers, Amer. Math. Monthly, 110(2003) 49–52; MR 2003k: 11006.
Michael S. Brandstein, New lower bound for a factor of an odd perfect number, #82T-10–240, Abstracts Amer. Math. Soc., 3 (1982) 257.
Richard P. Brent and Graeme L. Cohen, A new lower bound for odd perfect numbers, Math. Comput., 53 (1989) 431–437.
R. P. Brent, G. L. Cohen and H. J. J. te Riele, Improved techniques for lower bounds for odd perfect numbers, Math. Comput., 57(1991) 857–868; MR 92c: 1 1004.
E. Chein, An odd perfect number has at least 8 prime factors, PhD thesis, Penn. State Univ., 1979.
Chen Yi-Ze and Chen Xiao-Song, A condition for an odd perfect number to have at least 6 prime factors - 1 mod 3, Hunan Jiaoyu Xueyuan Xuebao (Ziran Kexue), 12(1994) 1–6; MR 96e: 1 1007.
Graeme L. Cohen, On the largest component of an odd perfect number, J. Austral. Math. Soc. Ser. A, 42(1987) 280–286.
Roger Cook, Factors of odd perfect numbers, Number Theory (Halifax NS, 1994) 123–131, CMS Conf. Proc., 15 Amer. Math. Soc., 1995; MR 96f: 1 1009.
Roger Cook, Bounds for odd perfect numbers, Number Theory (Ottawa ON, 1996) 67–71, CRM Proc. Lecture Notes, 19 Amer. Math. Soc., 1999; MR 2000d: 11010.
Simon Davis, A rationality condition for the existence of odd perfect numbers, Int. J. Math. Math. Sci, 2003 1261–1293; MR 2004b:11007.
John A. Ewell, On necessary conditions for the existence of odd perfect numbers, Rocky Mountain J. Math., 29 (1999) 165–175.
Aleksander Grytczuk and Marek W6jtowicz, There are no small odd perfect numbers, C.R. Acad. Sci. Paris Sér. I Math.328(1999) 1101–1105.
P. Hagis, Sketch of a proof that an odd perfect number relatively prime to 3 has at least eleven prime factors, Math. Comput.40(1983) 399–404.
P. Hagis, On the second largest prime divisor of an odd perfect number, Lecture Notes in Math., 899, Springer-Verlag, New York, 1971, pp. 254–263.
Peter Hagis and Graeme L. Cohen, Every odd perfect number has a prime factor which exceeds 106, Math. Comput, 67(1998) 1323–1330; MR 98k: 1 1002.
Judy A. Holdener, A theorem of Touchard on odd perfect numbers, Amer. Math. Monthly, 109(2002) 661–663; MR 2003d: 11012.
Douglas E. Iannucci, The second largest prime divisor of an odd perfect num-ber exceeds ten thousand, Math. Comput., 68(1999) 1749–1760; MR 2000i: 11200.
Douglas E. Iannucci, The third largest prime divisor of an odd perfect number exceeds one hundred, Math. Comput.69(2000) 867–879; MR 2000i:11201.
D. E. Iannucci and R. M. Sorli, On the total number of prime factors of an odd perfect number, Math. Comput.72(2003) 2077–2084; MR 2004b:11008.
Abd El-Hamid M. Ibrahim, On the search for perfect numbers, Bull. Fac.Sci. Alexandria Uuiv., 37 (1997) 93–95;
J. Inst. Math. Comput. Sci. Comput.Sci. Ser.,10(1999) 55–57.
Paul M. Jenkins, Odd perfect numbers have a prime factor exceeding 10 7 Math. Comput., 72(2003) 1549–1554; MR 2004a:11002.
Masao Kishore, Odd perfect numbers not divisible by 3 are divisible by at least ten distinct primes, Math. Comput., 31(1977) 274–279; MR 55 #2727.
Masao Kishore, Odd perfect numbers not divisible by 3. II, Math. Comput., 40(1983) 405–411; MR 84d:10009.
Masao Kishore, On odd perfect, quasiperfect, and odd almost perfect numbers, Math. Comput., 36(1981) 583–586; MR 82h:10006.
Pace P. Nielsen, An upper bound for odd perfect numbers, Elect. J. Combin. Number Theory,3(2003) A14. http://www.integers-ejcnt.org/vol3.html
J. Touchard, On prime numbers and perfect numbers, Scripta Math., 19(1953) 35–39; MR 14, 1063b.
M. D. Sayers, An improved lower bound for the total number of prime factors of an odd perfect number, M.App.Sc. Thesis, NSW Inst. Tech., 1986.
Paulo Starni, On the Euler’s factor of an odd perfect number, J. Number Theory, 37(1991) 366–369; MR 92a: 1 1010.
Paolo Starni, Odd perfect numbers: a divisor related to the Euler’s factor, J. Number Theory 44(1993) 58–59; MR 94c: 1 1003.
H. Abbott, C. E. Aull, Ezra Brown and D. Suryanarayana, Quasiperfect numbers, Acta Arith.,22(1973) 439–447; MR 47 #4915; corrections, 29(1976) 427428.
Leon Alaoglu and Paul Erdös, On highly composite and similar numbers, Trans. Amer. Math. Soc., 56(1944) 448–469; MR 6, 117b.
L. B. Alexander, Odd triperfect numbers are bounded below by 1060, M.A. thesis, East Carolina University, 1984.
M. M. Artuhov, On the problem of odd h-fold perfect numbers, Acta Arith., 23 (1973) 249–255.
Michael R. Avidon, On the distribution of primitive abundant numbers, Acta Arith.,77(1996) 195–205; MR 97g:11100.
Paul T. Bateman, Paul Erdös, Carl Pomerance and E.G. Straus, The arithmetic mean of the divisors of an integer, in Analytic Number Theory (Philadelphia, 1980) 197–220, Lecture Notes in Math.,899, Springer, Berlin - New York, 1981; MR 84b:10066.
Walter E. Beck and Rudolph M. Najar, A lower bound for odd triperfects, Math. Comput., 38 (1982) 249–251.
S. J. Benkoski, Problem E2308, Amer. Math. Monthly, 79 (1972) 774.
S. J. Benkoski and P. Erdös, On weird and pseudoperfect numbers, Math. Comput., 28(1974) 617–623; MR 50 #228; corrigendum, S. Kravitz, 29 (1975) 673.
Alan L. Brown, Multiperfect numbers, Scripta Math., 20(1954) 103–106; MR 16, 12.
E. A. Bugulov, On the question of the existence of odd multiperfect numbers (Russian), Kabardino-Balkarsk. Gos. Univ. Ucen. Zap., 30 (1966) 9–19.
David Callan, Solution to Problem 6616, Amer. Math. Monthly, 99 (1992) 783–789.
R. D. Carmichael and T. E. Mason, Note on multiply perfect numbers, including a table of 204 new ones and the 47 others previously published, Proc. Indiana Acad. Sci., 1911 257–270.
Paolo Cattaneo, Sui numeri quasiperfetti, Boll. Un. Mat. Ital.(3), 6(1951) 59–62; Zbl. 42, 268.
Cheng Lin-Feng, A result on multiply perfect number, J. Southeast Univ. (English Ed.), 18 (2002) 265–269.
Graeme L. Cohen, On odd perfect numbers II, multiperfect numbers and quasiperfect numbers, J. Austral. Math. Soc. Ser. A, 29(1980) 369–384; MR 81m: 10009.
Graeme L. Cohen, The non-existence of quasiperfect numbers of certain forms, Fibonacci Quart., 20 (1982) 81–84.
Graeme L. Cohen, On primitive abundant numbers, J. Austral. Math. Soc. Ser. A, 34(1983) 123–137.
Graeme L. Cohen, Primitive a-abundant numbers, Math. Comput., 43(1984) 263–270.
Graeme L. Cohen, Stephen Gretton and his multiperfect numbers, Internal Report No. 28, School of Math. Sciences, Univ. of Technology, Sydney, Australia, Oct 1991.
G. L. Cohen, Numbers whose positive divisors have small integral harmonic mean, Math. Comput., 66(1997) 883–891; MR 97f:11007.
G. L. Cohen and Deng Moujie, On a generalisation of Ore’s harmonic numbers, Nieuw Arch. Wisk.(4), 16(1998) 161–172; MR 2000k:11008.
G. L. Cohen and H. J. J. te Riele, Iterating the sum-of-divisors function, Experiment Math., 5(1996) 91–100; errata, 6(1997) 177; MR 97m:11007.
Graeme L. Cohen and Ronald M. Sorli, Harmonic seeds, Fibonacci Quart., 36(1998) 386–390; errata, 39(2001) 4; MR 99j:11002.
G. L. Cohen and P. Hagis, Results concerning odd multiperfect numbers, Bull. Malaysian Math. Soc., 8(1985) 23–26.
G. L. Cohen and M. D. Hendy, On odd multiperfect numbers, Math. Chronicle, 9(1980) 120–136; 10(1981) 57–61.
Philip L. Crews, Donald B. Johnson and Charles R. Wall, Density bounds for the sum of divisors function, Math. Comput.,26(1972) 773–777; MR 48 #6042; Errata 31(1977) 616; MR 55 #286.
J. T. Cross, A note on almost perfect numbers, Math. Mag.,47(1974) 230231.
Jean-Marie De Koninck and Aleksandar Ivié, On a sum of divisors problem, Publ. Inst. Math. (Beograd)(N.S.) 64(78)(1998) 9–20; MR 99m:11103.
Jean-Marie De Koninck and Imre Kdtai, On the frequency of k-deficient numbers, Publ. Math. Debrecen, 61(2002) 595–602; MR 2004a:11098.
Marc Deléglise, Encadrement de la densité des nombres abondants, (submitted).
P. Erdös, On the density of the abundant numbers, J. London Math. Soc., 9(1934) 278–282.
P. Erdös, Problems in number theory and combinatorics, Congressus Numerantium XVIII, Proc. 6th Conf. Numerical Math. Manitoba, 1976, 35–58 (esp. pp. 53–54); MR 80e: 10005.
Eswarathasan and E. Levine, p-integral harmonic sums, Discrete Math., 91(1991), 249–259; MR 93b:11039.
Benito Franqui and Mariano Garcia, Some new multiply perfect numbers, Amer. Math. Monthly, 60(1953) 459–462; MR 15, 101.
Benito Franqui and Mariano Garcia, 57 new multiply perfect numbers, Scripta Math., 20(1954) 169–171 (1955); MR 16, 447.
Mariano Garcia, A generalization of multiply perfect numbers, Scripte Math., 19(1953) 209–210; MR 15, 199.
Mariano Garcia, On numbers with integral harmonic mean, Amer. Math. Monthly, 61 (1954) 89–96; MR 15, 506d, 1140.
T. Goto and S. Shibata, All numbers whose positive divisors have integral harmonic mean up to 300, Math. Comput., 73(2004) 475–491.
Peter Hagis, The third largest prime factor of an odd multiperfect number exceeds 100, Bull. Malaysian Math. Soc., 9(1986) 43–49.
Peter Hagis, A new proof that every odd triperfect number has at least twelve prime factors, A tribute to Emil Grosswald: number theory and related analysis, 445–450 Contemp. Math., 143 Amer. Math. Soc., 1993. 43–49; MR 93e: 1 1003.
Peter Hagis and Graeme L. Cohen, Some results concerning quasiperfect numbers, J. Austral. Math. Soc. Ser. A, 33(1982) 275–286.
B. E. Hardy and M. V. Subbarao, On hyperperfect numbers, Proc. 13th Manitoba Conf. Numer. Math. Comput., Congressus Numerantium,42(1984) 183–198; MR 86c:11006.
Miriam Hausman and Harold N. Shapiro, On practical numbers, Comm. Pure Appl. Math.37(1984) 705–713; MR 86a:11036.
B. Hornfeck and E. Wirsing, Uber die Häufigkeit vollkommener Zahlen, Math. Ann., 133(1957) 431–438; MR 19, 837; see also 137(1959) 316–318; MR 21 #3389.
Aleksandar Ivie, The distribution of primitive abundant numbers, Studia Sci. Math. Hungar., 20(1985) 183–187; MR 88h:11065.
R. P. Jerrard and Nicholas Temperley, Almost perfect numbers, Math. Mag.,46 (1973) 84–87.
H.-J. Kanold, Uber mehrfach vollkommene Zahlen, J. reine angew. Math.,194(1955) 218–220; II 197(1957) 82–96; MR 17, 238; 18, 873.
H.-J. Kanold, Uber das harmonische Mittel der Teiler einer natürlichen Zahl, Math. Ann., 133(1957) 371–374; MR 19 635f.
H.-J. Kanold, Einige Bemerkungen über vollkommene und mehrfach vollkommene Zahlen, Abh. Braunschweig. Wiss. Ges., 42(1990/91) 49–55; MR 93c: 1 1002.
David G. Kendall, The scale of perfection, J. Appl. Probability, 19A(1982) 125–138; MR 83d:10007.
Masao Kishore, Odd triperfect numbers, Math. Comput., 42(1984) 231–233; MR 85d:11009.
Masao Kishore, Odd triperfect numbers are divisible by eleven distinct prime factors, Math. Comput. 44(1985) 261–263; MR 86k:11007.
Masao Kishore, Odd triperfect numbers are divisible by twelve distinct prime factors, J. Autral. Math. Soc. Ser. A, 42(1987) 173–182; MR 88c:11009.
Masao Kishore, Odd integers N with 5 distinct prime factors for which 2–10–12 a(N)/N 2 + 10–12, Math. Comput., 32 (1978) 303–309.
M. S. Klamkin, Problem E1445*, Amer. Math. Monthly, 67(1960) 1028; see also 82 (1975) 73.
Sidney Kravitz, A search for large weird numbers, J. Recreational Math., 9(1976–77) 82–85.
Richard Laatsch, Measuring the abundancy of integers, Math. Mag., 59 (1986) 84–92.
G. Lord, Even perfect and superperfect numbers, Elem. Math.,30(1975) 8788; MR 51 #10213.
Makowski, Remarques sur les fonctions 0(n), ¢(n) et u(n), Mathesis, 69(1960) 302–303.
Makowski, Some equations involving the sum of divisors, Elem. Math., 34(1979) 82; MR 81b:10004.
Wayne L. McDaniel, On odd multiply perfect numbers, Boll. Un. Mat. Ital. (4), 3(1970) 185–190; MR 41 #6764.
Guiseppe Melfi, On 5-tuples of twin practical numbers, Boll. Unione Mat. Ital. Sez. B Artic. Ric. Mat.(8), 2(1999) 723–734; MR 2000j:11138.
W. H. Mills, On a conjecture of Ore, Proc. Number Theory Conf., Boulder CO, 1972, 142–146.
D. Minoli, Issues in non-linear hyperperfect numbers, Math. Comput., 34 (1980) 639–645; MR 82c:10005.
Daniel Minoli and Robert Bear, Hyperperfect numbers, Pi Mu Epsilon J., 6#3(1974–75) 153–157.
Shigeru Nakamura, On k-perfect numbers (Japanese), J. Tokyo Univ. Merc. Marine(Nat. Sci.), 33(1982) 43–50.
Shigeru Nakamura, On some properties of o - (n), J. Tokyo Univ. Merc. Marine(Nat. Sci.), 35(1984) 85–93.
John C. M. Nash, Hyperperfect numbers. Period. Math. Hungar., 45 (2002) 121–122.
Oystein Ore, On the averages of the divisors of a number, Amer. Math. Monthly, 55(1948) 615–619; MR 10 284a.
Seppo Pajunen, On primitive weird numbers, A collection of manuscriptsrelated to the Fibonacci sequence,18th anniv vol., Fibonacci Assoc., 162–166.
Carl Pomerance, On a problem of Ore: Harmonic numbers (unpublished typescript); see Abstract *709-A5, Notices Amer. Math. Soc.,20(1973) A-648.
Carl Pomerance, On multiply perfect numbers with a special property, Pacific J. Math., 57 (1975) 511–517.
Carl Pomerance, On the congruences a(n) = a mod n and n - a mod 0(n), Acta Arith., 26(1975) 265–272.
Paul Poulet, La Chasse aux Nombres, Fascicule I, Bruxelles, 1929, 9–27.
Herwig Reidlinger, Über ungerade mehrfach vollkommene Zahlen [On odd multiperfect numbers], Osterreich. Akad. Wiss. Math.-Natur. Kl. Sitzungsber. II, 192(1983) 237–266; MR 86d: 1 1018.
Herman J. J. te Riele, Hyperperfect numbers with three different prime factors, Math. Comput., 36 (1981) 297–298.
Richard F. Ryan, A simpler dense proof regarding the abundancy index, Math. Mag., 76 (2003) 299–301.
J6zsef Sândor, On a method of Galambos and Kâtai concerning the frequency
of deficient numbers, Publ. Math. Debrecen,39(1991) 155–157; MR 92j:11111.
M. Satyanarayana, Bounds of a(N), Math. Student, 28 (1960) 79–81.
H. N. Shapiro, Note on a theorem of Dickson, Bull. Amer. Math. Soc., 55 (1949) 450–452.
H. N. Shapiro, On primitive abundant numbers, Comm. Pure Appl. Math., 21 (1968) 111–118.
W. Sierpinski, Sur les nombres pseudoparfaits, Mat. Vesnik,2(17)(1965) 212213; MR 33 #7296.
W. Sierpinski, Elementary Theory of Numbers (ed. A. Schinzel ), PWN—Polish Scientific Publishers, Warszawa, 1987, pp. 184–186.
R. Steuerwald, Ein Satz über natürlich Zahlen N mit a(N) = 3N, Arch. Math., 5(1954) 449–451; MR 16 113h.
D. Suryanarayana, Quasi-perfect numbers II, Bull. Calcutta Math. Soc., 69 (1977) 421–426; MR 80m: 10003.
Charles R. Wall, The density of abundant numbers, Abstract 73T—A184, Notices Amer. Math. Soc.,20(1973) A-472.
Charles R. Wall, A Fibonacci-like sequence of abundant numbers, Fibonacci Quart., 22(1984) 349; MR 86d: 1 1018.
Charles R. Wall, Phillip L. Crews and Donald B. Johnson, Density bounds for the sum of divisors function, Math. Comput., 26 (1972) 773–777.
Paul A. Weiner, The abundancy ratio, a measure of perfection, Math. Mag., 73 (2000) 307–310.
Motoji Yoshitake, Abundant numbers, sum of whose divisors is equal to an integer times the number itself (Japanese), Szigaku Seminar, 18 (1979) no. 3, 50–55.
Andreas and Eleni Zachariou, Perfect, semi-perfect and Ore numbers, Bull. Soc. Math. Grèce(N.S.),13(1972) 12–22; MR 50 #12905.
K. Alladi, On arithmetic functions and divisors of higher order, J. Austral. Math. Soc. Ser. A, 23(1977) 9–27.
Eckford Cohen, Arithmetical functions associated with the unitary divisors of an integer, Math. Z., 74(1960) 66–80; MR 22 #3707.
Eckford Cohen, The number of unitary divisors of an integer, Amer. Math. Monthly, 67(1960) 879–880; MR 23 # Al24.
Graeme L. Cohen, On an integer’s infinitary divisors, Math. Comput., 54 (1990) 395–411.
Graeme Cohen and Peter Hagis, Arithmetic functions associated with the infinitary divisors of an integer, Internat. J. Math. Math. Sci.,(to appear).
J. L. DeBoer, On the non-existence of unitary perfect numbers of certain type, Pi Mu Epsilon J. (submitted).
H. A. M. Frey, Uber unitär perfekte Zahlen, Elem. Math., 33(1978) 95–96; MR 81a: 10007.
S. W. Graham, Unitary perfect numbers with squarefree odd part, Fibonacci Quart., 27(1989) 317–322; MR 90i:11003.
Peter Hagis, Lower bounds for unitary multiperfect numbers, Fibonacci Quart., 22(1984) 140–143; MR 85j:11010.
Peter Hagis, Odd nonunitary perfect numbers, Fibonacci Quart, 28 (1990) 11–15; MR 90k:11006.
Peter Hagis and Graeme Cohen, Infinitary harmonic numbers, Bull. Austral. Math. Soc., 41(1990) 151–158; MR 91d:11001.
J6zsef Sândor, On Euler’s arithmetical function, Proc. Alg. Conf. Brasov 1988, 121–125.
V. Sitaramaiah and M. V. Subbarao, On unitary multiperfect numbers, Nieuw Arch. Wisk.(4), 16(1998) 57–61; MR 99h:11008.
V. Siva Rama Prasad and D. Ram Reddy, On unitary abundant numbers, Math. Student, 52(1984) 141–144 (1990) MR 91m:11002.
V. Siva Rama Prasad and D. Ram Reddy, On primitive unitary abundant numbers, Indian J. Pure Appl. Math, 21(1990) 40–44; MR 91f: 11004.
M. V. Subbarao, Are there an infinity of unitary perfect numbers? Amer. Math. Monthly, 77(1970) 389–390.
M. V. Subbarao and D. Suryanarayana, Sums of the divisor and unitary divisor functions, J. reine angew. Math., 302(1978) 1–15; MR 80d:10069.
M. V. Subbarao and L. J. Warren, Unitary perfect numbers, Canad. Math. Bull., 9(1966) 147–153; MR 33 #3994.
M. V. Subbarao, T. J. Cook, R. S. Newberry and J. M. Weber, On unitary perfect numbers, Delta, 3#1(Spring 1972) 22–26.
D. Suryanarayana, The number of k-ary divisors of an integer, Monatsh. Math., 72(1968) 445–450.
Charles R. Wall, The fifth unitary perfect number, Canad. Math. Bull., 18(1975) 115–122. See also Notices Amer. Math. Soc., 16(1969) 825.
Charles R. Wall, Unitary harmonic numbers, Fibonacci Quart, 21 (1983) 18–25.
Charles R. Wall, On the largest odd component of a unitary perfect number, Fibonacci Quart., 25(1987) 312–316; MR 88m:11005.
J. Alanen, O. Ore and J. G. Stemple, Systematic computations on amicable umbers, Math. Comput.,21(1967) 242–245; MR 36 #5058.
M. M. Artuhov, On some problems in the theory of amicable numbers (Russian), Acta Arith., 27 (1975) 281–291.
S. Battiato, Ober die Produktion von 37803 neuen befreundeten Zahlenpaaren mit der Briitermethode, Master’s thesis, Wuppertal, June 1988.
Stefan Battiato and Walter Borho, Breeding amicable numbers in abundance II, Math. Comput., 70(2001) 1329–1333; MR 2002b: 11011.
S. Battiato and W. Borho, Are there odd amicable numbers not divisible by three? Math. Comput., 50(1988) 633–636; MR 89c: 1 1015.
W. Borho, On Thabit ibn Kurrah’s formula for amicable numbers, Math. Comput., 26 (1972) 571–578.
W. Borho, Befreundete Zahlen mit gegebener Primteileranzahl, Math. Ann., 209 (1974) 183–193.
W. Borho, Eine Schranke für befreundete Zahlen mit gegebener Teileranzahl, Math. Nachr., 63 (1974) 297–301.
W. Borho, Some large primes and amicable numbers, Math. Comput., 36 (1981) 303–304.
W. Borho and H. Hoffmann, Breeding amicable numbers in abundance, Math. Comput., 46 (1986) 281–293.
P. Bratley and J. McKay, More amicable numbers, Math. Comput.,22(1968) 677–678; MR 37 #1299.
P. Bratley, F. Lunnon and J. McKay, Amicable numbers and their distribution, Math. Comput., 24 (1970) 431–432.
H. Brown, A new pair of amicable numbers, Amer. Math. Monthly 46 (1939) 345.
Graeme L. Cohen, Stephen F. Gretton and Peter Hagis, Multiamicable numbers, Math. Comput., 64(1995) 1743–1753; MR 95m:11012.
Graeme L. Cohen and H. J. J. te Riele, On ’-amicable pairs, Math. Comput., 67(1998) 399–411; MR 98d:11009.
Patrick Costello, Four new amicable pairs, Notices Amer. Math. Soc, 21 (1974) A-483.
Patrick Costello, Amicable pairs of Euler’s first form, Notices Amer. Math. Soc., 22(1975) A-440.
Patrick Costello, Amicable pairs of the form (i, 1), Math. Comput., 56(1991) 859–865; MR 91k:11009.
Patrick Costello, New amicable pairs of type (2,2) and type (3,2), Math. Comput., 72(2003) 489–497; MR 2003i:11006.
P. Erdüs, On amicable numbers, Publ. Math. Debrecen, 4(1955) 108–111; MR 16, 998.
P. Erdös and G. J. Rieger, Ein Nachtrag über befreundete Zahlen, J. reine angew. Math., 273(1975) 220.
E. B. Escott, Amicable numbers, Scripta Math., 12(1946) 61–72; MR 8, 135.
L. Euler, De numeris amicabilibus, Opera Omnia, Ser.1, Vol.2, Teubner, Leipzig and Berlin, 1915, 63–162.
M. Garcia, New amicable pairs, Scripta Math.23(1957) 167–171; MR 20 #5158.
Mariano Garcia, New unitary amicable couples, J. Recreational Math.,17 (1984–5) 32–35.
Mariano Garcia, Favorable conditions for amicability, Hostos Community Coll. Math. J., New York, Spring 1989, 20–25.
Mariano Garcia, K-fold isotopic amicable numbers, J. Recreational Math., 19(1987) 12–14.
Mariano Garcia, New amicable pairs of Euler’s first form with greatest common factor a prime times a power of 2, Nieuw Arch. Wisk.(4),17(1999) 25–27; MR 2000d:11158.
Mariano Garcia, A million new amicable pairs, J. Integer seq.,4(2001) no.2 Article 01.2.6 3pp.(electronic).
Mariano Garcia, The first known type (7,1) amicable pair, Math. Comput., 72(2003) 939–940; MR 2003j:11007.
A. Gioia and A. M. Vaidya, Amicable numbers with opposite parity, Amer. Math. Monthly,74(1967) 969–973; correction 75(1968) 386; MR 36 #3711, 37 #1306.
Peter Hagis, On relatively prime odd amicable numbers, Math. Comput., 23(1969) 539–543; MR 40 #85.
Peter Hagis, Lower bounds for relatively prime amicable numbers of opposite parity, Math. Comput., 24(1970) 963–968.
Peter Hagis, Relatively prime amicable numbers of opposite parity, Math. Mag., 43(1970) 14–20.
Peter Hagis, Unitary amicable numbers, Math. Comput., 25 (1971) 915–918.
H.-J. Kanold, Über die Dichten der Mengen der vollkommenen und der befreundeten Zahlen, Math. Z., 61(1954) 180–185; MR 16, 337.
-J. Kanold, Über befreundete Zahlen I, Math. Nachr., 9(1953) 243–248; II ibid., 10 (1953) 99–111; MR 15, 506.
J. Kanold, Über befreundete Zahlen III, J. reine angew. Math.,234(1969) 207–215; MR 39 #122.
E. J. Lee, Amicable numbers and the bilinear diophantine equation, Math. Comput.,22(1968) 181–187; MR 37 #142.
E. J. Lee, On divisibility by nine of the sums of even amicable pairs, Math. Comput.,23(1969) 545–548; MR 40 #1328.
E. J. Lee and J. S. Madachy, The history and discovery of amicable numbers, part 1, J. Recreational Math.,5(1972) 77–93; part 2, 153–173; part 3, 231–249.
Ore, Number Theory and its History, McGraw-Hill, New York, 1948, p. 89.
Carl Pomerance, On the distribution of amicable numbers, J. reine angew. Math.,293/294(1977) 217–222; II 325(1981) 183–188; MR 56 #5402, 82m: 10012.
P. Poulet, 43 new couples of amicable numbers, Scripta Math., 14 (1948) 77.
H. J. J. te Riele, Four large amicable pairs, Math. Comput., 28 (1974) 309–312.
H. J. J. te Riele, On generating new amicable pairs from given amicable pairs, Math. Comput., 42 (1984) 219–223.
Herman J. J. te Riele, New very large amicable pairs, in Number Theory Noordwijkerhout 1983, Springer Lecture Notes in Math., 1068 (1984) 210–215.
H. J. J. te Riele, Computation of all the amicable pairs below 1010, Math.Comput.,47(1986) 361–368 and S9—S40.
H. J. J. te Riele, A new method for finding amicable pairs, in Mathematics of Computation 19.13–1993 (Vancouver, 1993), Proc. Sympos. Appl. Math. 48(1994) 577–581; MR 95m: 1 1013.
H. J. J. te Riele, W. Borho, S. Battiato, H. Hoffmann and E.J. Lee, Table of Amicable Pairs between 1010 and 1052, Centrum voor Wiskunde en Informatica, Note NM-N8603, Stichting Math. Centrum, Amsterdam, 1986.
Charles R. Wall, Selected Topics in Number Theory, Univ. of South Carolina Press, Columbia SC, 1974, P. 68.
Dale Woods, Construction of amicable pairs, #789–10–21, Abstracts Amer. Math. Soc., 3 (1982) 223.
S. Y. Yan, 68 new large amicable pairs, Comput. Math. Appl., 28(1994) 7174; MR 96a:11008; errata, 32(1996) 123–127; MR 97h: 1 1005.
S. Y. Yan and T. H. Jackson, A new large amicable pair, Comput. Math. Appl., 27(1994) 1–3; MR 94m: 1 1012.
Walter E. Beck and Rudolph M. Najar, Fixed points of certain arithmetic functions, Fibonacci Quart., 15(1977) 337–342; Zbl. 389. 10005.
Walter E. Beck and Rudolph M. Najar, Reduced and augmented amicable pairs to 108, Fibonacci Quart., 31(1993) 295–298; MR 94g: 1 1005.
Peter Hagis and Graham Lord, Quasi-amicable numbers, Math. Comput.,31 (1977) 608–611; MR 55 #7902; Zbl. 355.10010.
M. Lal and A. Forbes, A note on Chowla’s function, Math. Comput., 25(1971) 923–925; MR 45 #6737; Zbl. 245. 10004.
Andrzej Makowski, On some equations involving functions 0(n) and o - (n), Amer. Math. Monthly,67(1960) 668–670; correction 68(1961) 650; MR 24 #A76.
Jack Alanen, Empirical study of aliquot series, Math. Rep., 133 Stichting Math. Centrum Amsterdam, 1972; see Math. Comput., 28(1974) 878–880.
Manuel Benito, Wolfgang Creyaufmüller, Juan L. Varona and Paul Zimmermann, Aliquot sequence 3630 ends after reaching 100 digits, Experiment Math., 11(2002) 201–206; MR 2003j: 11150.
Manuel Benito and Juan L. Varona, Advances in aliquot sequences, Math. Comput.,68(1999) 389–393; MR 99c:11162.
E. Catalan, Propositions et questions diverses, Bull. Soc. Math. France, 16 (1887–88) 128–129.
John Stanley Devitt, Aliquot Sequences, MSc thesis, The Univ. of Calgary, 1976; see Math. Comput., 32(1978) 942–943.
J. S. Devitt, R. K. Guy and J. L. Selfridge, Third report on aliquot sequences, Congr. Numer. XVIII, Proc. 6th Manitoba Conf. Numer. Math., 1976, 177–204; MR 80d: 10001.
L. E. Dickson, Theorems and tables on the sum of the divisors of a number, Quart. J. Math., 44(1913) 264–296.
Paul Erdös, On asymptotic properties of aliquot sequences, Math. Comput., 30(1976) 641–645.
Andrew W. P. Guy and Richard K. Guy, A record aliquot sequence, in Mathematics of Computation 1943–1993 (Vancouver, 1993), Proc. Sympos. Appl. Math., ( 1994 ) Amer. Math. Soc., Providence RI, 1984.
Richard K. Guy, Aliquot sequences, in Number Theory and Algebra, Academic Press, 1977, 111–118; MR 57 #223; Zbl. 367.10007.
Richard K. Guy and J. L. Selfridge, Interim report on aliquot sequences, Congr. Numer. V, Proc. Conf. Numer. Math., Winnipeg, 1971, 557–580; MR 49 #194; Zbl. 266. 10006.
Richard K. Guy and J. L. Selfridge, Combined report on aliquot sequences, The Univ. of Calgary Math. Res. Rep. 225(May, 1974 ).
Richard K. Guy and J. L. Selfridge, What drives an aliquot sequence? Math. Comput., 29(1975) 101–107; MR 52 #5542; Zbl. 296.10007. Corrigendum, ibid., 34(1980) 319–321; MR 81f:10008; Zbl. 423. 10005.
Richard K. Guy and M. R. Williams, Aliquot sequences near 1012, Congr. Numer. XII, Proc. 4th Manitoba Conf. Numer. Math., 1974, 387–406; MR 52 #242; Zbl. 359. 10007.
Richard K. Guy, D. H. Lehmer, J. L. Selfridge and M. C. Wunderlich, Second report on aliquot sequences, Congr. Numer. IX, Proc. 3rd Manitoba Conf. Numer. Math., 1973, 357–368; MR 50 #4455; Zbl. 325. 10007.
H. W. Lenstra, Problem 6064, Amer. Math. Monthly, 82(1975) 1016; solution 84 (1977) 580.
G. Aaron Paxson, Aliquot sequences (preliminary report), Amer. Math. Monthly, 63(1956) 614. See also Math. Comput., 26 (1972) 807–809. P. Poulet, La chasse aux nombres, Fascicule I, Bruxelles, 1929.
P. Poulet, Nouvelles suites arithmétiques, Sphinx, Deuxième Année (1932) 53–54.
H. J. J. te Riele, A note on the Catalan-Dickson conjecture, Math. Comput., 27(1973) 189–192; MR 48 #3869; Zbl. 255. 10008.
H. J. J. te Riele, Iteration of number theoretic functions, Report NN 30/83, Math. Centrum, Amsterdam, 1983.
Paul Erdös, A mélange of simply posed conjectures with frustratingly elusive solutions, Math. Mag., 52 (1979) 67–70.
P. Erdös, Problems and results in number theory and graph theory, Congressus Numerantium 27, Proc. 9th Manitoba Conf. Numerical Math. Comput., 1979, 3–21.
Richard K. Guy and Marvin C. Wunderlich, Computing unitary aliquot sequences–a preliminary report, Congressus Numerantium 27, Proc. 9th Manitoba Conf. Numerical Math. Comput., 1979, 257–270.
P. Hagis, Unitary amicable numbers, Math. Comput.,25(1971) 915–918; MR 45 #8599.
Peter Hagis, Unitary hyperperfect numbers, Math. Comput.,36(1981) 299301.
M. Lal, G. Tiller and T Summers, Unitary sociable numbers, Congressus Numerantium 7,Proc. 2nd Manitoba Conf. Numerical Math., 1972, 211–216: MR 50 #4471.
Rudolph M. Najar, The unitary amicable pairs up to 108, Internat. J. Math. Math. Sci., 18(1995) 405–410; MR 96c: 1 1011.
H. J. J. to Riele, Unitary Aliquot Sequences, MR139/72, Mathematisch Centrum, Amsterdam, 1972; reviewed Math. Comput., 32(1978) 944–945; Zbl. 251. 10008.
H. J. J. to Riele, Further Results on Unitary Aliquot Sequences, NW12/73, Mathematisch Centrum, Amsterdam, 1973; reviewed Math. Comput., 32 (1978) 945.
H. J. J. to Riele, A Theoretical and Computational Study of Generalized Aliquot Sequences,MCT72, Mathematisch Centrum, Amsterdam, 1976; reviewed Math. Comput.,32(1978) 945–946; MR 58 #27716.
R. Wall, Topics related to the sum of unitary divisors of an integer, PhD thesis, Univ. of Tennessee, 1970.
Dieter Bode, Über eine Verallgemeinerung der volkommenen Zahlen, Dissertation, Braunschweig, 1971.
G. G. Dandapat, J. L. Hunsucker and C. Pomerance, Some new results on odd perfect numbers, Pacific J. Math.,57(1975) 359–364; 52 #5554.
P. Erdös, Some remarks on the iterates of the cß and a functions, Colloq. Math., 17 (1967) 195–202.
J. L. Hunsucker and C. Pomerance, There are no odd super perfect numbers less than 7. 1024, Indian J. Math., 17(1975) 107–120; MR 82b: 10010.
H.-J. Kanold, Über “Super perfect numbers,” Elem. Math.,24(1969) 61–62; MR 39 #5463.
Graham Lord, Even perfect and superperfect numbers, Elem. Math., 30 (1975) 87–88.
Helmut Maier, On the third iterates of the 0- and a-functions, Colloq. Math., 49 (1984) 123–130.
Andrzej Makowski, On two conjectures of Schinzel, Elem. Math., 31 (1976) 140–141.
Schinzel, Ungelöste Probleme Nr. 30, Elem. Math., 14 (1959) 60–61.
V. Sitaramaiah and M. V. Subbarao, On the equation a* (a* (n)) = 2n, Utilitas Math., 53(1998) 101–124; MR 99a: 1 1009.
Suryanarayana, Super perfect numbers, Elem. Math.,24(1969) 16–17; MR 39 #5706.
Suryanarayana, There is no superperfect number of the form p2’, Elern. Math.,28(1973) 148–150; MR 48 #8374.
P. Erdös, Über die Zahlen der Form a(n) - n and n - 0(n), Elem. Math.,28(1973) 83–86; MR 49 #2502.
Paul Erdös, Some unconventional problems in number theory, Astérisque, 61(1979) 73–82; MR 81h: 10001.
Nicolae Ciprian Bonciocat, Congruences for the convolution of divisor sum function, Bull. Greek Math. Soc., 46(2002) 161–170; MR 2003e: 11111.
P. Erdös, Remarks on number theory II: some problems on the a function, Acta Arith.,5(1959) 171–177; MR 21 #6348.
Mihaly Bencze, A contest problem and its application (Hungarian), Mat. Lapok Ifjûscigi Foly6irat (Romania), 91 (1986) 179–186.
J.-M. De Koninck, On the solutions of a2(n) = a2(n + t), Ann. Univ. Sci. Budapest. Sect. Comput., 21(2002) 127–133; MR 2003h: 11007.
Richard K. Guy and Daniel Shanks, A constructed solution of a(n) = a(n +1), Fibonacci Quart.,12(1974) 299; MR 50 #219.
Pentti Haukkanen, Some computational results concerning the divisor functions d(n) and a(n), Math. Student, 62(1993) 166–168; MR 90j: 1 1006.
John L. Hunsucker, Jack Nebb Si Robert E. Stearns, Computational results concerning some equations involving a(n), Math. Student, 41 (1973) 285–289.
W. E. Mientka and R. L. Vogt, Computational results relating to problems concerning a(n), Mat. Vesnik, 7 (1970) 35–36.
Erd6s, On arithmetical properties of Lambert series, J. Indian Math. Soc.(N.S.) 12 (1948) 63–66.
P. Erdös, On the irrationality of certain series: problems and results, in New Advances in Transcendence Theory, Cambridge Univ. Press, 1988, pp. 102–109.
P. Erd6s and M. Kac, Problem 4518, Amer. Math. Monthly 60(1953) 47. Solution R. Breusch, 61 (1954) 264–265.
M. Sugunamma, PhD thesis, Sri Venkataswara Univ., 1969.
N. C. Ankeny, E. Artin and S. Chowla, The class-number of real quadratic number fields, Ann. of Math.(2), 56(1952) 479–493; MR 14, 251.
R. C. Baker and J. Brüdern, On sums of two squarefull numbers, Math. Proc. Cambridge Philos. Society, 116(1994) 1–5; MR 95f: 1 1073.
P. T. Bateman and E. Grosswald, On a theorem of Erdös and Szekeres, Illinois J. Math., 2 (1958) 88–98.
B. D. Beach, H. C. Williams and C. R. Zarnke, Some computer results on units in quadratic and cubic fields, Proc. 25th Summer Meet. Canad. Math. Congress, Lakehead, 1971, 609–648; MR 49 #2656.
Cai Ying-Chun, On the distribution of square-full integers, Acta Math. Sinica (N.S.) 13(1997) 269–280; MR 98j: 1 1070.
Catalina Calderon and M. J. Velasco, Waring’s problem on squarefull numbers, An. Univ. Bucuregti Mat., 44 (1995) 3–12.
Cao Xiao-Dong, The distribution of square-full integers, Period. Math. Hun-gar., 28(1994) 43–54; MR 95k: 1 1119.
J. H. E. Cohn, A conjecture of Erdös on 3-powerful numbers. Math. Comput., 67(1998) 439–440; MR 98c:11104.
David Drazin and Robert Gilmer, Complements and comments, Amer. Math. Monthly, 78(1971) 1104–1106 (esp. p. 1106).
W. Duke, Hyperbolic distribution problems and half-integral weight Maass forms, Invent. Math., 92(1988) 73–90; MR 89d:11033.
P. Erdös, Problems and results on consecutive integers, Eureka, 38(1975–76) 3–8.
P. Erdös and G. Szekeres, Über die Anzahl der Abelschen Gruppen gegebener Ordnung und über ein verwandtes zahlentheoretisches Problem, Acta Litt. Sci. Szeged, 7(1934) 95–102; Zbl. 10, 294.
S. W. Golomb, Powerful numbers, Amer. Math. Monthly, 77(1970) 848–852; MR 42 #1780.
Ryuta Hashimoto, Ankeny-Artin-Chowla conjecture and continued fraction expansion, J. Number Theory, 90(2001) 143–153; MR 2002e:11149.
D. R. Heath-Brown, Ternary quadratic forms and sums of three square-full numbers, Séminaire de Théorie des Nombres, Paris, 1986–87, Birkhäuser, Boston, 1988; MR 91b: 1 1031.
D. R. Heath-Brown, Sums of three square-full numbers, in Number Theory, I (Budapest, 1987 ), Colloq. Math. Soc. Janos Bolyai, 51(1990) 163–171; MR 91i: 11036.
D. R. Heath-Brown, Square-full numbers in short intervals, Math. Proc. Cambridge Philos. Soc., 110(1991) 1–3; MR 92c:11090.
M.N. Huxley and O. Trifonov, The square-full numbers in an interval, Math. Proc. Cambridge Philos. Soc., 119(1996) 201–208; MR 96k:11114.
Aleksander Ivie, On the asymptotic formulas for powerful numbers, Publ. Math. Inst. Beograd (N.S.), 23(37)(1978) 85–94; MR 58 #21977.
Ivié and P. Shiue, The distribution of powerful integers, Illinois J. Math., 26(1982) 576–590; MR 84a:10047.
H. Iwaniec, Fourier coefficients of modular forms of half-integral weight, Invent. Math., 87(1987) 385–401; MR 88b:11024.
C.-H. Jia, On square-full numbers in short intervals, Acta Math. Sinica (N.S.) 5(1987) 614–621.
Ekkehard Krätzel, On the distribution of square-full and cube-full numbers, Monatsh. Math., 120(1995) 105–119; MR 96f:11116.
Hendrik W. Lenstra, Solving the Pell equation, Notices Amer. Math. Soc., 49(2002) 182–192.
Liu Hong-Quan, On square-full numbers in short intervals, Acta Math. Sinica (N.S.), 6(1990) 148–164; MR 91g:11105.
Liu Hong-Quan, The number of squarefull numbers in an interval, Acta Arith., 64(1993) 129–149.
Liu Hong-Quan, The number of cube-full numbers in an interval, Acta Arith., 67(1994) 1–12; MR 95h:11100.
Liu Hong-Quan, The distribution of 4-full numbers, Acta Arith., 67(1994) 165–176.
Liu Hong-Quan, The distribution of square-full numbers, Ark. Mat., 32(1994) 449–454; MR 97a:11146.
Andrzej Makowski, On a problem of Golomb on powerful numbers, Amer. Math. Monthly, 79(1972) 761.
Andrzej Makowski, Remarks on some problems in the elementary theory of numbers, Acta Math. Univ. Comenian., 50/51(1987) 277–281; MR 90e:11022.
Wayne L. McDaniel, Representations of every integer as the difference of powerful numbers, Fibonacci Quart., 20 (1982) 85–87.
H. Menzer, On the distribution of powerful numbers, Abh. Math. Sem. Univ. Hamburg, 67(1997) 221–237; MR 98h:11115.
Richard A. Mollin, The power of powerful numbers, Internat. J. Math. Math. Sci., 10(1987) 125–130; MR 88e:11008.
Richard A. Mollin and P. Gary Walsh, On non-square powerful numbers, Fibonacci Quart., 25(1987) 34–37; MR 88f:11006.
Richard A. Mollin and P. Gary Walsh, On powerful numbers, Internat. J. Math. Math. Sci., 9(1986) 801–806; MR 88f:11005.
Richard A. Mollin and P. Gary Walsh, A note on powerful numbers, quadratic fields and the Pellian, CR Math. Rep. Acad. Sci. Canada, 8(1986) 109–114; MR 87g: 1 1020.
Richard A. Mollin and P. Gary Walsh, Proper differences of non-square powerful numbers, CR Math. Rep. Acad. Sci. Canada, 10(1988) 71–76; MR 89e:11003.
L. J. Mordell, On a pellian equation conjecture, Acta Arith., 6(1960) 137–144; MR 22 #9470.
B. Z. Moroz, On representation of large integers by integral ternary positive definite quadratic forms, Journées Arithmétiques (Geneva 1991, Astérisque, 209(1992), 15, 275–278; MR 94a: 1 1051.
Abderrahmane Nitaj, On a conjecture of Erdios on 3-powerful numbers, Bull. London Math. Soc., 27(1995) 317–318; MR 96b:11045.
R. W. K. Odoni, On a problem of Erdös on sums of two squarefull numbers, Acta Arith., 39(1981) 145–162; MR 83c:10068.
Laurentiu Panaitopol, On square free integers, Bull. Math. Soc. Sci. Math. Roumanie (N.S.), 43(91)(2000) 19–23; MR.2002k:11156.
J. van der Poorten, H. J. J. te Riele and H. C. Williams, Computer verification of the Ankeny-Artin-Chowla conjecture for all primes less than 100 000 000 000, Math. Comput., 70(2001) 1311–1328; MR 2001j:11125; corrigenda and addition, 72(2003) 521–523; MR 2003g: 11162.
V. M. Prasad and V. V. S. Sastri, An asymptotic formula for partitions into square full numbers, Bull. Calcutta Math. Soc., 86(1993) 403–408; MR 96b: 1 1138.
Peter Georg Schmidt, On the number of square-full integers in short intervals, Acta Arith., 50(1988) 195–201; corrigendum, 54(1990) 251–254; MR 89f: 1 1131.
R. Seibold and E. Krätzel, Die Verteilung der k-vollen und l-freien Zahlen, Abh. Math. Sem. Univ. Hamburg, 68(1998) 305–320.
W. A. Sentance, Occurrences of consecutive odd powerful numbers, Amer. Math. Monthly, 88(1981) 272–274.
P. Shiue, On square-full integers in a short interval, Glasgow Math. J., 25 (1984) 127–134.
P. Shiue, The distribution of cube-full numbers, Glasgow Math. J., 33(1991) 287–295. MR 92g: 1 1091.
P. Shiue, Cube-full numbers in short intervals, Math. Proc. Cambridge Philos. Soc., 112 (1992) 1–5; MR 93d: 1 1097.
J. Stephens and H. C. Williams, Some computational results on a problem concerning powerful numbers, Math. Comput., 50 (1988) 619–632.
Sury, On a conjecture of Chowla et al., J. Number Theory, 72(1998) 137139; it MR 99f: 1 1005.
Suryanarayana, On the distribution of some generalized square-full integers, Pacific J. Math, 72(1977) 547–555; MR 56 #11933.
Suryanarayana and R. Sitaramachandra Rao, The distribution of square-full integers, Ark. Mat, 11(1973) 195–201; MR 49 #8948.
Charles Vanden Eynden, Differences between squares and powerful numbers, *816–11–305, Abstracts Amer. Math. Soc., 6 (1985) 20.
David T. Walker, Consecutive integer pairs of powerful numbers and related Diophantine equations, Fibonacci Quart, 14(1976) 111–116; MR 53 #13107.
Wu Jiel, On the distribution of square-full and cube-full integers, Monatsh. Math, 126(1998) 339–358.
Wu Jiel, On the distribution of square-full integers, Arch. Math. (Basel), 77(2001) 233–240; MR 2002g:11136.
Yu Gang’, The distribution of 4-full numbers, Monatsh. Math., 118(1994) 145–152; MR 95i: 1 1101.
Yuan Ping-Zhi, On a conjecture of Golomb on powerful numbers (Chinese. English summary), J. Math. Res. Exposition, 9(1989) 453–456; MR 91c: 1 1009.
G. Straus and M. V. Subbarao, On exponential divisors, Duke Math. J, 41(1974) 465–471; MR 50 #2053.
M. V. Subbarao, On some arithmetic convolutions, Proc. Conf. Kalamazoo MI, 1971, Springer Lecture Notes in Math, 251(1972) 247–271; MR 49 #2510.
M. V. Subbarao and D. Suryanarayana, Exponentially perfect and unitary perfect numbers, Notices Amer. Math. Soc., 18 (1971) 798.
P. Erdös, Problem P. 307, Canad. Math. Bull., 24 (1981) 252.
Paul Erdös and Hugh L. Montgomery, Sums of numbers with many divisors, J. Number Theory, 75(1999) 1–6; MR 99k: 1 1153.
Anthony D. Forbes, Fifteen consecutive integers with exactly four prime factors, Math. Comput., 71(2002) 449–452; MR 2002g: 11012.
P. Erdös and L. Mirsky, The distribution of values of the divisor function d(n), Proc. London Math. Soc.(3), 2 (1952) 257–271.
P. Erdös, C. Pomerance and A. Sârközy, On locally repeated values of certain arithmetic functions, II, Acta Math. Hungarica, 49(1987) 251–259; MR 88c: 1 1008.
J. Fabrykowski and M. V. Subbarao, Extension of a result of Erdös concerning
the divisor function, Utilitas Math, 38(1990) 175–181; MR 92d:11101.
D. R. Heath-Brown, A parity problem from sieve theory, Mathematika, 29
-6 (esp. p. 6).
D. R. Heath-Brown, The divisor function at consecutive integers, Mathematika, 31 (1984) 141–149.
Adolf Hildebrand, The divisors function at consecutive integers, Pacific J. Math., 129 (1987) 307–319; MR 88k: 1 1062.
J. Hildebrand, Erdös’ problems on consecutive integers, Paul Erdös and his mathematics, I (Budapest, 1999) 305–317, Bolyai Soc. Math. Stud., 11, Janos Bolyai Math. Soc., Budapest, 2002; MR 2004b: 11142.
Kan Jia-Hai and Shan Zun, On the divisor function d(n), Mathematika, 43(1997) 320–322; II 46(1999) 419–423; MR 98b: 11101; 2003c: 11122.
M. Nair and P. Shiue, On some results of Erdös and Mirsky, J. London Math. Soc.(2), 22(1980) 197–203; and see ibid., 17 (1978) 228–230.
Pinner, M.Sc. thesis, Oxford, 1988.
Schinzel, Sur un problème concernant le nombre de diviseurs d’un nombre naturel, Bull. Acad. Polon. Sci. Ser. sci. math. astr. phys., 6 (1958) 165–167.
Schinzel and W. Sierpinski, Sur certaines hypothèses concernant les nombres premiers, Acta Arith., 4 (1958) 185–208.
W. Sierpinski, Sur une question concernant le nombre de diviseurs premiers d’un nombre naturel, Colloq. Math., 6 (1958) 209–210.
OEIS: A000005, A005237–005238, A006558, A006601, A019273, A039665, A049051.
Alan Baker, Logarithmic forms and the abc-conjecture, Number Theory (Eger), 1996, de Gruyter, Berlin, 1998, 37–44; MR 99e: 1 1101.
Frits Beukers, The Diophantine equation Ax° + By 4 = Cz’, Duke Math. J., 91(1998) 61–88: MR 99f: 1 1039.
Niklas Broberg, Some examples related to the abc-conjecture for algebraic number fields, Math. Comput., 69(2000) 1707–1710; MR 2001a:11117.
Jerzy Browkin and Juliusz Brzezinski, Some remarks on the abc-conjecture, Math. Comput., 62(1994) 931–939; MR 94g:11021.
Jerzy Browkin, Michael Filaseta, G. Greaves and Andrzej Schinzel, Squarefree values of polynomials and the abc-conjecture, Sieve methods, exponential sums, and their applications in number theory (Cardiff 1995 ) 65–85, London Math. Soc. Lecture Note Ser., 237, Cambridge Univ. Press, 1997.
Juliusz Brzezinski, ABC on the abc-conjecture, Normat, 42(1994) 97–107; MR 95h:11024.
Cao Zhen-Fu, A note on the Diophantine equation a + by = cz, Acta Arith., 91(1999) 85–93; MR 2000m:11029.
Cao Zhen-Fu and Dong Xiao-Lei, The Diophantine equation, Proc. Japan Acad. Ser. A Math. Sci., 77(2001) 1–4; MR 2002c: 11027.
Cao Zhen-Fu, Dong Xiao-Lei and Li Zhong, A new conjecture concerning the Diophantine equation x2+by = cz, Proc. Japan Acad. Ser. A Math. Sci., 78 (2002) 199–202.
Todd Cochran and Robert E. Dressler, Gaps between integers with the same prime factors, Math. Comput., 68(1999) 395–401; MR 99c:11118.
Henri Darmon, Faltings plus epsilon, Wiles plus epsilon, and the generalized Fermat equation, C. R. Math. Rep. Acad. Sci. Canada, 19(1997) 3–14; corrigendum, 64; MR 98h:11034ab.
Henri Darmon and Andrew Granville, On the equations. Bull. London Math. Soc., 27(1995) 513–543; MR 96e: 1 1042.
Michael Filaseta and Sergei Konyagin, On a limit point associated with the abc-conjecture, Colloq. Math., 76(1998) 265–268; MR 99b: 1 1029.
Andrew Granville, ABC allows us to count squarefrees, Internat. Math. Res. Notices, 1998 991–1009.
Andrew Granville and Thomas J. Tucker, It’s as easy as abc, Notices Amer. Math. Soc., 49(2002) 1224–1231; MR 2003f:11044.
Alain Kraus, On the equation a survey. Ramanujan J., 3(1999), no. 3, 315–333; MR 2001f:11046.
Serge Lang, Old and new conjectured diophantine inequalities, Bull. Amer. Math. Soc., 23(1990) 37–75.
Serge Lang, Die abc-Vermutung, Elem. Math., 48 (1993) 89–99; MR 94g: 1 1044.
Michel Langevin, Cas d’égalité pour le théorème de Mason et applications de la conjecture (abc), C. R. Acad. Sci. Paris Sér I math., 317(1993) 441–444; MR 94k: 1 1035.
Michel Langevin, Sur quelques conséquences de la conjecture (abc) en arithmétique et en logique, Rocky Mountain J. Math., 26(1996) 1031–1042; MR 97k: 1 1052.
Le Mao-Hua, The Diophantine equation x 2 +Dm = p’, Acta Arith., 52(1989) 255–265; MR 90j:11029.
Le Mao-Hua, A note on the Diophantine equation x 2 + by = cz, Acta Arith., 71(1995) 253–257; MR 96d:11037.
Allan I. Liff, On solutions of the equation x a+yb = zC, Math. Mag, 41(1968) 174–175; MR 38 #5711.
W. Masser, On abc and discriminants, Proc. Amer. Math. Soc., 130(2002) 3141–3150.
R. Daniel Mauldin, A generalization of Fermat’s last theorem: the Beal conjecture and prize problem, Notices Amer. Math. Soc., 44(1997) 1436–1437; MR 98j:11020 (quoted above).
Abderrahmane Nitaj, An algorithm for finding good abc-examples, C. R. Acad. Sci. Paris Sér I math., 317(1993) 811–815.
Abderrahmane Nitaj, Algorithms for finding good examples for the abc and Szpiro conjectures, Experiment. Math., 2(1993) 223–230; MR 95b:11069.
Abderrahmane Nitaj, La conjecture abc, Enseign. Math., (2) 42(1996) 3–24; MR 97a: 1 1051.
Abderrahmane Nitaj, Aspects expérimentaux de la conjecture abc, Number Theory (Paris 1993–1994), 145–156, London Math. Soc. Lecture Note Ser., 235, Cambridge Univ. Press, 1996; MR 99f:11041.
Makowski, On a problem of Erdös, Enseignement Math.(2), 14(1968) 193. J. Oesterlé, Nouvelles approches du “thre” de Fermat, Sém. Bourbaki, 2/88, exposé #694.
Bjorn Poonen, Some Diophantine equations of the form , Acta Arith., 86(1998) 193–205; MR 99h:11034.
Paulo Ribenboim, On square factors of terms in binary recurring sequences and the ABC-conjecture, Publ. Math. Debrecen, 59 (2001) 459–469.
Paulo Ribenboim and Peter Gary Walsh, The ABC-conjecture and the powerful part of terms in binary recurring sequences, J. Number Theory, 74(1999) 134147; MR 99k: 1 1047.
L. Stewart and Yu Kun-Rui, On the abc-conjecture, Math. Ann., 291(1991) 225–230; MR 92k:11037; II, Duke Math. J., 108(2001) 169–181; MR 2002e: 11046.
Nobuhiro Terai, The Diophantine equation a’+by = cz, I, II, III, Proc. Japan Acad. Ser. A Math. Sci., 70(1994) 22–26; 71(1995) 109–110; 72(1996) 20–22; MR 95b:11033; 96m:11022; 98a:11038.
R. Tijdeman, The number of solutions of Diophantine equations, in Number Theory, II (Budapest, 1987), Colloq. Math. Soc. Jcinos Bolyai, 51(1990) 671–696.
Paul Vojta, A more general abc-conjecture, Internat. Math. Res. Notices, 1998 1103–1116; MR 99k:11096.
Yuan Ping-Zhi and Wang Jia-Bao, On the Diophantine equation x 2 + by = cz, Acta Arith., 84(1998) 145–147.
Hans Riesel, En Bok om Primtal (Swedish), Lund, 1968; supplement Stockholm, 1977; MR 42 #4507, 58 #10681.
Hans Riesel, Prime Numbers and Computer Methods for Factorization, Progress in Math., 126, Birkhäuser, 2nd ed. 1994.
Robert Baillie, New primes of the form k 2 + 1, Math. Comput., 33(1979) 1333–1336; MR 80h: 10009.
Robert Baillie, G. V. Cormack and H. C. Williams, The problem of Sierpinski concerning k • 2 + 1 Math. Comput., 37(1981) 229–231; corrigendum, 39 (1982) 308.
Wieb Bosma, Explicit primality criteria for h•2/`+1, Math. Comput., 61 (1993) 97–109.
A. Buell and J. Young, Some large primes and the Sierpinski problem, SRC Technical Report 88–004, Supercomputing Research Center, Lanham MD, May 1988.
V. Cormack and H. C. Williams, Some very large primes of the form k • 2’ + 1, Math. Comput., 35(1980) 1419–1421; MR 81i:10011; corrigendum, Wilfrid Keller, 38(1982) 335; MR 82k:10011.
Michael Filaseta, Coverings of the integers associated with an irreducibility theorem of A. Schinzel, Number Theory for the Millenium, II (Urbana IL, 2000) 1–24, AKPeters, Natick MA, 2002; MR 2003k:11015.
Anatoly S. Izotov, A note on Sierpinski numbers, Fibonacci Quart., 33(1995) 206–207; MR 96f:11020.
Jaeschke, On the smallest k such that all , Math. Comput., 40(1983) 381–384; MR 84k:10006; corrigendum, 45(1985) 637; MR 87b:11009.
Wilfrid Keller, Factors of Fermat numbers and large primes of the form, Math. Comput., 41(1983) 661–673; MR 85b:11119; II (incomplete draft, 92–02-19).
Wilfrid Keller, Woher kommen die größten derzeit bekannten Primzahlen? Mitt. Math. Ges. Hamburg, 12(1991) 211–229;MR 92j:11006.
N. S. Mendelsohn, The equation 0(x) = k, Math. Mag., 49(1976) 37–39; MR 53 #252.
Raphael M. Robinson, A report on primes of the form k•2 + 1 and on factors of Fermat numbers, Proc. Amer. Math. Soc., 9(1958) 673–681; MR 20 #3097.
J. L. Selfridge, Solution of problem 4995, Amer. Math. Monthly, 70 (1963) 101.
W. Sierpinski, Sur un problème concernant les nombres k • 2’ + 1, Elem. Math., 15(1960) 73–74; MR 22 #7983; corrigendum, 17(1962) 85.
W. Sierpinski, 250 Problems in Elementary Number Theory, Elsevier, New York, 1970, Problem 118, pp. 10 and 64.
R. G. Stanton, Further results on covering integers of the form 1 + k * 2` v by primes, Combinatorial mathematics, VIII (Geelong, 1980), Springer Lecture Notes in Math., 884(1981) 107–114; MR 84j:10009.
R. G. Stanton and H. C. Williams, Further results on covering of the integers 1 + k2m by primes, Combinatorial Math. VIII, Lecture Notes in Math., 884, Springer-Verlag, Berlin-New York, 1980, 107–114.
Yong Gao-Chen, On integers of the forms kr - 2 n and kr2m + 1, J. Number Theory, 98(2003) 310–319; MR bf2003m:11004.
K. Alladi and C. Grinstead, On the decomposition of n! into prime powers, J. Number Theory, 9(1977) 452–458; MR 56 #11934.
Daniel Berend, On the parity of exponents in the factorization of n!, J. Number Theory, 64(1997) 13–19; MR 98g: 1 1019.
Chen Yong-Gao, On the parity of exponents in the standard factorization of n!, J. Number Theory, 100(2003) 326–331; MR 2004b: 11136.
Chen Yong-Gao and Zhu Yao-Chen, On the prime power factorization of n! J. Number Theory, 82(2000) 1–11; MR 2001c: 11027.
P. Erdös, Some problems in number theory, Computers in Number Theory, Academic Press, London and New York, 1971, 405–414.
Paul Erdös, S. W. Graham, Aleksandar Ivie and Carl Pomerance, On the number of divisors of n!, Analytic Number Theory, Vol. 1(Allerton Park IL, 1995) 337–355, Progr. Math., 138, Birkhäuser Boston, 1996; MR 97d: 1 1142.
Florian Luca and Pantelimon Stänicä, On the prime power factorization of n! J. Number Theory, 102 (2003) 298–305.
J. W. Sander, On the parity of exponents in the prime factorization of factorials, J. Number Theory, 90(2001) 316–328; MR 2002j: 11105.
Chris Caldwell, The Diophantine equation, J. Recreational Math., 26 (1994) 128–133.
Donald I. Cartwright and Joseph Kupka, When factorial quotients are integers, Austral. Math. Soc. Gaz., 29 (2002) 19–26.
Earl Ecklund and Roger Eggleton, Prime factors of consecutive integers, Amer. Math. Monthly, 79(1972) 1082–1089.
E. Ecklund, R. Eggleton, P. Erdös and J. L. Selfridge, on the prime factorization of binomial coefficients, J. Austral. Math. Soc. Ser. A, 26(1978) 257–269; MR 80e:10009.
P. Erdös, Problems and results on number theoretic properties of consecutive integers and related questions, Congressus Numerantium XVI (Proc. 5th Manitoba Conf. Numer. Math. 1975 ), 25–44.
P. Erdös and R. L. Graham, On products of factorials, Bull. Inst. Math. Acad. Sinica, Taiwan, 4 (1976) 337–355.
T. N. Shorey, On a conjecture that a product of k consecutive positive integers is never equal to a product of mk consecutive positive integers except and related questions, Number Theory (Paris, 1992–1993), L.M.S. Lect. Notes 215(1995) 231–244; MR 96g: 1 1028.
Neil J. Calkin and Andrew Granville, On the number of co-prime-free sets, Number Theory (New York, 1991–1995), Springer, New York, 1996, 9–18; MR 97j:11006.
P. J. Cameron and P. Erdös, On the number of sets of integers with various properties, Number Theory (Banff, 1988), de Gruyter, Berlin, 1990, 61–79; MR 92g: 1 1010.
P. Erdös, On a problem in elementary number theory and a combinatorial problem, Math. Comput, (1964) 644–646; MR 30 #1087.
Kenneth Lebensold, A divisibility problem, Studies in Appl. Math, 56(197677) 291–294; MR 58 #21639.
Emma Lehmer, Solution to Problem 3820, Amer. Math. Monthly, 46 (1939) 240–241.
P. T. Bateman and R. M. Stemmler, Waring’s problem for algebraic number fields and primes of the form (pr -1)/(pd -1), Illinois J. Math, 6(1962) 142–156; MR 25 #2059.
Ted Chinburg and Melvin Henriksen, Sums of kth powers in the ring of polynomials with integer coefficients, Bull. Amer. Math. Soc, 81(1975) 107–110; MR 51 #421; Acta Arith, 29(1976) 227–250; MR 53 #7942.
Karl Dilcherand Josh Knauer, On a conjecture of Feit and Thompson, (preprint, Williams60, Banff, May 2003 ).
Makowski and A. Schinzel, Sur l’équation indéterminée de R. Goormaghtigh, Mathesis, 68(1959) 128–142; MR 22 # 9472; 70 (1965) 94–96.
N. M. Stephens, On the Feit-Thompson conjecture, Math. Comput, 25(1971) 625; MR 45 #6738.
Neil J. Calkin and Andrew Granville, On the number of coprime-free sets, Number Theory (New York, 1991–1995) 9–18, Springer, New York, 1996; MR 97j: 1 1006.
S. L. G. Choi, The largest subset in [1, n] whose integers have pairwise 1.c.m. not exceeding n, Mathematika, 19(1972) 221–230; 47 #8461.
S. L. G. Choi, On sequences containing at most three pairwise coprime integers, Trans. Amer. Math. Soc, 183(1973) 437–440; 48 #6052.
P. Erdös, Extremal problems in number theory, Proc. Sympos. Pure Math. Amer. Math. Soc, 8(1965) 181–189; MR 30 #4740.
P. Erdös and J. L. Selfridge, Some problems on the prime factors of consecutive integers, Illinois J. Math., 11 (1967) 428–430.
Schinzel, Unsolved problem 31, Elem. Math., 14 (1959) 82–83.
Alfred Brauer, On a property of k consecutive integers, Bull. Amer. Math. Soc., 47(1941) 328–331; MR 2, 248.
Ronald J. Evans, On blocks of N consecutive integers, Amer. Math. Monthly 76 (1969) 48–49.
Ronald J. Evans, On N consecutive integers in an arithmetic progression, Acta Sci. Math. Univ. Szeged, 33(1972) 295–296; MR 47 #8408.
Heiko Harborth, Eine Eigenschaft aufeinanderfolgender Zahlen, Arch. Math. (Basel) 21(1970) 50–51; MR 41 #6771.
Heiko Harborth, Sequenzen ganzer Zahlen, Zahlentheorie (Tagung, Math. Forschungsinst. Oberwolfach, 1970) 59–66; MR 51 #12775.
S. S. Pillai, On m consecutive integers I, Proc. Indian Acad. Sci. Sect. A, 11(1940) 6–12; MR 1, 199; II 11(1940) 73–80; MR 1, 291; III 13(1941) 530–533; MR 3, 66; IV Bull. Calcutta Math. Soc, 36(1944) 99–101; MR 6, 170.
D. H. Lehmer, On a problem of Stormer, Illinois J. Math, 8(1964) 57–79; MR 28 #2072.
P. Erdös and Jan Turk, Products of integers in short intervals, Acta Arith., 44(1984) 147–174; MR 86d: 1 1073.
Paul Erdös, Janice Malouf, John Selfridge and Esther Szekeres, Subsets of an interval whose product is a power, Paul Erds memorial collection. Discrete Math., 200(1999) 137–147; MR 2000e: 11017.
Jan-Hendrik Evertse and J. H. Silverman, Uniform bounds for the number of solutions to Y’2 = f (X) Math. Proc. Cambridge Philos. Soc, 100(1986) 237–248; MR 87k:11034.
L. Hajdu and Akos Pintér, Square product of three integers in short intervals, Math. Comput., 68(1999) 1299–1301; 99j: 1 1027.
Michel Langevin, Cas d’égalité pour le théorème de Mason et applications de la conjecture (abc), C.R. Acad. Sci. Paris Sér. I Math., 317(1993) 441–444; MR 94j: 1 1027.
T. N. Shorey, Perfect powers in products of integers from a block of consecutive integers, Acta Arith., 49(1987) 71–79; MR 88m: 1 1002.
T. N. Shorey and Yu. V. Nesterenko, Perfect powers in products of integers from a block of consecutive integers, II Acta Arith., 76(1996) 191–198; MR 97d: 1 1005.
For other problems and results on the divisors of binomial coefficients, see B33.
Emre Alkan, Variations on Wolstenholme’s theorem, Amer. Math. Monthly, 101 (1994) 1001–1004.
D. F. Bailey, Two p3 variations of Lucas’s theorem, J. Number Theory, 35(1990) 208–215; MR 90f: 1 1008.
M. Bayat, A generalization of Wolstenholme’s theorem, Amer. Math. Monthly, 104(1997) 557–560 (but see Gessel reference).
Daniel Berend and Jorgen E. Harmse, On some arithmetical properties of middle binomial coefficients, Acta Arith., 84 (1998) 31–41.
Cai Tian-Xin and Andrew Granville, On the residues of binomisl coefficients and their residues modulo prime powers. Acta Math. Sin. (Engl. Ser.), 18(2002) 277–288.
Chen Ke-Ying, Another equivalent form of Wolstenholme’s theorem and its generalization (Chinese), Math. Practice Theory, 1995 71–74; MR 97d: 1 1006.
Paul Erdös, C. B. Lacampagne and J. L. Selfridge, Estimates of the least prime factor of a binomial coefficient, Math. Comput., 61(1993) 215 224; MR 93k: 1 1013.
P. Erdös and J. L. Selfridge, Problem 6447, Amer. Math. Monthly 90(1983) 710; 92 (1985) 435–436.
P. Erdös and G. Szekeres, Some number theoretic problems on binomial coefficients, Austral. Math. Soc. Gaz., 5(1978) 97–99; MR 80e:10010 is uninformative.
Ira M. Gessel, Wolstenholme revisited, Amer. Math. Monthly, 105(1998) 657658; MR 99e:11009.
Andrew Granville, Arithmetic properties of binomial coefficients. I. Binomial coefficients modulo prime powers, Organic mathematics (Burnaby BC, 1995), CMS Conf. Proc., 20(1997) 253–276; MR 99h: 1 1016.
Andrew Granville, On the scarcity of powerful binomial coefficients, Mathematika 46(1999) 397–410; MR 2002b:11029.
Andrew Granville and Olivier Ramaré, Explicit bounds on exponential sums and the scarcity of squarefree binomial coefficients, Mathematika, 43(1996) 73107; MR 99m:11023.
Grytczuk, On a conjecture of Erdös on binomial coefficients, Studia Sci. Math. Hungar., 29(1994) 241–244.
Hong Shao-Fang, A generalization of Wolstenholme’s theorem, J. South China Normal Univ. Natur. Sci. Ed., 1995 24–28; MR 99f:11004.
Gerhard Larcher, On the number of odd binomial coefficients, Acta Math. Hungar., 71(1996 183–203.
Lee Dong-Hoonl and Hahn Sang-Geun, Some congruences for binomial coefficients, Class field theory-its centenary and prospect (Tokyo, 1998) 445–461
Adv. Stud. Pure Math. 30 Math. Soc. Japan, Tokyo, 2001; II Proc. Japan Acad. Ser. A Math. Sci, 76(2000) 104–107; MR 2002k:11024, 11025.
Grigori Kolesnik, Prime power divisors of multinomial and q-multinomial coefficients, J. Number Theory, 89(2001) 179–192; MR 2002i:11020.
Richard F. Lukes, Renate Scheidler and Hugh C. Williams, Further tabulation of the Erdös-Selfridge function, Math. Comput., 66(1997) 1709–1717; MR 98a: 1 1191.
Richard J. McIntosh, A generalization of a congruential property of Lucas, Amer. Math. Monthly, 99(1992) 231–238.
Richard J. McIntosh, On the converse of Wolstenholme’s theorem, Acta Arith., 71(1995) 381–389; MR 96h:11002.
Marko Razpet, On divisibility of binomial coefficients, Discrete Math., 135 (1994) 377–379; MR 95j:11014.
Harry D. Ruderman, Problem 714, Crux Math., 8(1982) 48; 9 (1983) 58.
J. W. Sander, On prime divisors of binomial coefficients. Bull. London Math. Soc.j 24(1992) no. 2 140–142; MR 93g:11019.
J. W. Sander, Prime power divisors of multinomial coefficients and Artin’s conjecture, J. Number Theory, 46(1994) 372–384; MR 95a:11018.
J. W. Sander, On the order of prime powers dividing (2n ), Acta Math., 174(1995) 85–118; MR 96b:11018.
J. W. Sander, A story of binomial coefficients and primes, Amer. Math. Monthly, 102(1995) 802–807; MR 96m:11015.
Renate Scheidler and Hugh C. Williams, A method of tabulating the number-theoretic function g(k), Math. Comput., 59(1992) 199, 251–257; MR 92k: 1 1146.
David Segal, Problem E435, partial solution by H.W. Brinkman, Amer. Math. Monthly, 48 (1941) 269–271.
P. Erdös, Problems and results in combinatorial analysis and combinatorial number theory, in Proc. 9th S.E. Conf. Combin. Graph Theory, Comput., Boca Raton, Congressus Numerantium XXI, Utilitas Math. Winnipeg, 1978, 29–40.
P. Erdös and C. Pomerance, Matching the natural numbers up to n with distinct multiples in another interval, Nederl. Akad. Wetensch. Proc. Ser. A, 83(= Indag. Math., 42)(1980) 147–161; MR 81i: 10053.
Paul Erdös and Carl Pomerance, An analogue of Grimm’s problem of finding distinct prime factors of consecutive integers, Utilitas Math., 24(1983) 45–46; MR 85b: 1 1072.
P. Erdös and J. L. Selfridge, Some problems on the prime factors of consecutive integers II, in Proc. Washington State Univ. Conf. Number Theory, Pullman, 1971, 13–21.
A. Grimm, A conjecture on consecutive composite numbers, Amer. Math. Monthly, 76 (1969) 1126–1128.
Michel Langevin, Plus grand facteur premier d’entiers en progression arithmétique, Sém. Delange-Pisot-Poitou, 18(1976/77) Théorie des nombres: Fasc. 1, Exp. No. 3, Paris, 1977; MR 81a: 10011.
Carl Pomerance, Some number theoretic matching problems, in Proc. Number Theory Conf., Queen’s Univ., Kingston, 1979, 237–247.
Carl Pomerance and J. L. Selfridge, Proof of D.J. Newman’s coprime mapping conjecture, Mathematika, 27(1980) 69–83; MR 81i: 10008.
K. Ramachandra, T. N. Shorey and R. Tijdeman, On Grimm’s problem relating to factorization of a block of consecutive integers, J. reine angew. Math., 273 (1975) 109–124.
E. F. Ecklund, On prime divisors of the binomial coefficient, Pacific J. Math., 29 (1969) 267–270.
P. Erdös, A theorem of Sylvester and Schur, J. London Math. Soc., 9 (1934) 282–288.
Paul Erdös, A mélange of simply posed conjectures with frustratingly elusive solutions, Math. Mag., 52 (1979) 67–70.
P. Erdös and R. L. Graham, On the prime factors of (z), Fibonacci Quart., 14 (1976) 348–352.
P. Erdös, R. L. Graham, I. Z. Ruzsa and E. Straus, On the prime factors of (t’’), Math. Comput, 29(1975) 83–92. n
M. Faulkner, On a theorem of Sylvester and Schur, J. London Math. Soc., 41 (1966) 107–110.
Henry W. Gould, Advanced Problem 5777*, Amer. Math. Monthly, 78 (1971) 202.
Henry W. Gould and Paula Schlesinger, Extensions of the Hermite G.C.D. theorems for binomial coefficients, Fibonacci Quart., 33(1995) 386–391; MR 97g: 1 1015.
Hansraj Gupta, On the parity of (n + m — 1)!(n, m) /n!m!, Res. Bull. Panjab Univ. (N.S.), 20(1969) 571–575; MR 43 #3201.
L. Moser, Insolvability of Canad. Math. Bull, 6(1963)167–169.
P. A. Picon, Intégrité de certains produits-quotients de factorielles, Séminaire Lotharingien de Combinatoire (Saint-Nabor, 1992), Publ. Inst. Rech. Math. Av., 498, 109–113; MR 95j: 1 1013.
P. A. Picon, Conditions d’intégrité de certains coefficients hypergéometriques: généralisation d’un théorème de Landau, Discrete Math., 135(1994) 245–263; MR 96f: 1 1015.
J. W. Sander, Prime power divisors of (2, 7), J. Number Theory, 39(1991) 65–74; MR 92i: 1 1097.
J. W. Sander, Prime power divisors of binomial coefficients, J. reine angew. Math., 430(1992) 1–20; MR 93h:11021; reprise 437 (1993) 217–220.
J. W. Sander, On primes not dividing binomial coefficients, Math. Proc. Cambridge Philos. Soc., 113(1993) 225–232; MR 93m: 1 1099.
J. W. Sander, An asymptotic formula for ath powers dividing binomial coefficients, Mathematika, 39(1992) 25–36; MR 93i: 1 1110.
J. W. Sander, On primes not dividing binomial coefficients, Math. Proc. Cambridge Philos. Soc., 113 (1993) 225–232.
Sârközy, On divisors of binomial coefficients I, J. Number Theory, 20(1985) 70–80; MR 86c: 1 1002.
Schur, Einige Sätze über Primzahlen mit Anwendungen und Irreduzibilitätsfragen I, S.-B. Preuss, Akad. Wiss. Phys.-Math. Kl., 14 (1929) 125–136.
Sun Zhi-Wei, Products of binomial coefficients modulo p 2 Acta Arith., 97(2001) 87–98; MR 2002m: 11013.
Sylvester, On arithmetical series, Messenger of Math, 21(1892) 1–19,87— 120.
W. Utz, A conjecture of Erdös concerning consecutive integers, Amer. Math. Monthly, 68 (1961) 896–897.
Velammal, Is the binomial coefficient (2’) squarefree? Hardy-Ramanujan J., 18(1995) 23–45; MR 95j: 1 1016.
E. Burbacka and J. Piekarczyk, P. 217, R. 1, Colloq. Math., 10 (1963) 365.
Schinzel, Sur un problème de P. Erdös, Colloq. Math, 5(1957–58) 198–204.
P. Erdös, How many pairs of products of consecutive integers have thesame prime factors? Amer. Math. Monthly 87 (1980) 391–392.
M. Aldaz, A. Bravo, S. Gutiérrez and A. Ubis, A theorem of D. J. Newman on Euler’s 0 function and arithmetic progressions. Amer. Math. Monthly, 108(2001) 364–367; MR 2002i: 11099.
Robert Baillie, Table of 5(n) = cb(n + 1), Math. Comput., 30(1976) 189–190. Roger C. Baker and Glyn Harman, Sparsely totient numbers, Ann. Fac. Sci. Toulouse Math.(6), 5(1996) 183–190; MR 97k: 1 1129.
David Ballew, Janell Case and Robert N. Higgins, Table of 0(n) = 0(n + 1), Math. Comput., 29 (1975) 329–330.
Jerzy Browkin and Andrzej Schinzel, On integers not of the form n - rb(n), Colloq. Math., 58(1995) 55–58; MR 95m: 1 1106.
Jôzsef Bukor and Jânos T. Toth, Estimation of the mean value of some arithmetical functions, Octogon Math. Mag., 3(1995) 31–32; MR 97a: 1 1013.
Cai Tian-Xin, On Euler’s equation 0(x) = k, Adv. Math. (China), 27 (1998) 224–226.
Thomas Dence and Carl Pomerance, Euler’s function in residue classes, Ramanujan J., 2(1998) 7–20; MR 99k: 1 1148.
Michael W. Ecker, Problem E-1, The AMATYC Review, 5(1983) 55; comment 6(1984)55.
N. El-Kassar, On the equations kcb(n) = cb(n + 1) and kc/r(n + 1) = 0(n), Number theory and related topics (Seoul 1998) 95–109, Yonsei Univ. Inst. Math. Sci., Seoul 2000; MR 2003g: 11001.
P. Erdös, Über die Zahlen der Form a•(n) — n und n — 0(n), Elem. Math., 28 (1973) 83–86.
P. Erdös and R. R. Hall, Distinct values of Euler’s 0-function, Mathematika, 23 (1976) 1–3.
S. W. Graham, Jeffrey J. Holt and Carl Pomerance, On the solutions to 0(n) = 0(n + k). Number theory in progress, Vol. 2 (Zakopane-Koicielisko, 1997), 867882, de Gruyter, Berlin, 1999; MR 2000h: 11102.
Jeffrey J. Holt, The minimal number of solutions to 0(n) =.rb(n + k), Math. Comput., 72(2003) 2059–2061; MR 2004c:11171.
Patricia Jones, On the equation 0(x) + 0(k) = 0(x + k), Fibonacci Quart., 28(1990) 162–165; MR 91e:11008.
M. Lal and P. Gillard, On the equation 0(n) = 0(n + k), Math. Comput., 26(1972) 579–582.
Antanas Laurinéikas, On some problems related to the Euler 0-function, Paul Erdôs and his mathematics (Budapest, 1999 ) 152–154, Janos Bolyai Math. Soc., Budapest 1999.
Florian Luca and Carl Pomerance, On some problems of Makowski-Schinzel and Erdös concerning the arithmetic functions 0 and a, Colloq. Math. 92(2002) 111–130; MR 2003e: 11105.
Helmut Maier and Carl Pomerance, On the number of distinct values of Euler’s 0-function, Acta Arith., 49(1988) 263–275.
Andrzej Makowski, On the equation ç(n+k) = 20(n), Elem. Math., 29 (1974) 13.
Greg Martin, The smallest solution of 0(30n + 1) 0(30n) is…, Amer. Math. Monthly, 106(1999) 449–452; MR 2000d:11011.
Kathryn Miller, UMT 25, Math. Comput., 27 (1973) 447–448.
Donald J. Newman, Euler’s 0-function on arithmetic progressions, Amer. Math. Monthly, 104(1997) 256–257; MR 97m:11010.
Laurent l iu Panaitopol, On some properties concerning the function a(n) = n — c/o(n), Bull. Greek Math. Soc., 45(2001) 71–77; MR 2003k:11008.
Laurentiu Panaitopol, On the equation n — 0(n) = m, Bull. Math. Soc. Sci. Math. Roumanie (N.S.), 44(92)(2001) 97–100.
Jan-Christoph Puchta, On the distribution of totients, Fibonacci Quart., 40(2002) 68–70.
HermanJ. J. te Riele, On the size of solutions of the inequality, Public-key cryptography and computational number theory (Warsaw, 2000) 249–255, de Gruyter, Berlin, 2001; MR 2003c: 11007.
Schinzel, Sur l’équation 0(x + k) = 0(x), Acta Arith., 4(1958) 181–184; MR 21 #5597.
Schinzel and A. Wakulicz, Sur l’équation 0(x + k) = 0(x) II, Acta Arith., 5(1959) 425–426; MR 23 #A831.
W. Sierpiriski, Sur un propriété de la fonction ¢(n), Publ. Math. Debrecen, 4 (1956) 184–185.
Mladen Vassilev-Missana, The numbers which cannot be values of Euler’s function q5, Notes Number Theory Discrete Math., 2(1996) 41–48; MR 97m:11012.
Charles R. Wall, Density bounds for Euler’s function, Math. Comput., 26 (1972) 779–783 with microfiche supplement; MR 48 #6043.
Masataka Yorinaga, Numerical investigation of some equations involving Euler’s 0-function, Math. J. Okayama Univ., 20 (1978) 51–58.
Zhang Ming-Zhi, On nontotients, J. Number Theory, 43(1993) 168–173; MR 94c:11004.
Ronald Alter, Can W(n) properly divide n — 1? Amer. Math. Monthly 80 (1973) 192–193.
L. Cohen and P. Hagis, On the number of prime factors of n if 0(n)In–1, Nieuw Arch. Wisk. (3), 28 (1980) 177–185.
G. L. Cohen Si S. L. Segal, A note concerning those n for which W(n) + 1 divides n, Fibonacci Quart, 27(1989)285–286.
Aleksander Grytczuk and Marek Wdjtowicz, On a Lehmer problem concerning Euler’s totient function, Proc. Japan Acad. Ser. A Math. Sci. 79 (2003) 136–138.
Masao Kishore, On the equation kç(M) = M–1, Nieuw Arch. Wisk. (3), 25(1977) 48–53; see also Notices Amer. Math. Soc., 22 (1975) A501–502.
H. Lehmer, On Euler’s totient function, Bull. Amer. Math. Soc., 38 (1932) 745–751.
Lieuwens, Do there exist composite numbers for which kç(M) = M — 1 holds? Nieuw Arch. Wisk. (3), 18(1970) 165–169; MR 42 #1750.
R. J. Miech, An asymptotic property of the Euler function, Pacific J. Math, 19(1966) 95–107; MR 34 #2541.
Carl Pomerance, On composite n for which ç(n)In- 1, Acta Arith, 28(1976) 387–389; II
Pacific J. Math, 69(1977) 177–186; MR 55 #7901; see also Notices Amer. Math. Soc, 22(1975) A542.
J6zsef Sândor, On the arithmetical functions ak (n) and qk (n), Math. Student, 58(1990) 49–54; MR 91h: 1 1005.
Fred. Schuh, Can n–1 be divisible by q(n) when n is composite? Mathematica, Zutphen B, 12 (1944) 102–107.
V. Siva Rama Prasad Si M. Rangamma, On composite n satisfying a problem of Lehmer, Indian J. Pure Appl. Math., 16(1985) 1244–1248; MR 87g: 1 1017.
V. Siva Rama Prasad and M. Rangamma, On composite n for which (n) In-1, Nieuw Arch. Wisk. (4), 5(1987) 77–81; MR 88k: 1 1008.
M. V. Subbarao, On two congruences for primality, Pacific J. Math, 52(1974) 261–268; MR 50 #2049.
M. V. Subbarao, On composite n satisfying W(n) - 1 mod n,Abstract 88211–60 Abstracts Amer. Math. Soc., 14 (1993) 418.
M. V. Subbarao, The Lehmer problem on the Euler totient: a Pandora’s box of unsolvable problems, Number theory and discrete mathematics (Chandigarh, 2000 ) 179–187.
David W. Wall, Conditions for (/)(N) to properly divide N — 1, A Collection of Manuscripts Related to the Fibonacci Sequence, 18th Anniv. Vol., Fibonacci Assoc., 205–208.
Shan Zun, On composite n for which 0(n)In - 1, J. China Univ. Sci. Tech., 15(1985) 109–112; MR 87h: 1 1007.
Jean-Marie De Koninck, Problem 10966(b), Amer. Math. Monthly, 109 (2002) 759.
Le Mao-Hua, A note on primes p with a(pm) = zn, Colloq. Math., 62 (1991) 193–196.
R. D. Carmichael, Note on Euler’s 0-function, Bull. Amer. Math. Soc., 28 (1922) 109–110; and see 13(1907) 241–243.
P. Erdös, On the normal number of prime factors of p — 1 and some other related problems concerning Euler’s 0-function, Quart. J. Math. Oxford Ser., 6 (1935) 205–213.
P. Erdös, Some remarks on Euler’s 0-function and some related problems, Bull. Amer. Math. Soc., 51(1945) 540–544.
P. Erdös, Some remarks on Euler’s 0-function, Acta Arith., 4(1958) 10–19; MR 22#1539.
Kevin Ford, The distribution of totients, Ramanujan J., 2(1998) 67–151; MR 99m:11106.
Kevin Ford, The distribution of totients, Electron. Res. Announc. Amer. Math. Soc., 4(1998) 27–34; MR 99f:11125.
Lorraine L. Foster, Solution to problem E3361, Amer. Math. Monthly 98 (1991) 443.
Peter Hagis, On Carmichael’s conjecture concerning the Euler phi function (Italian summary), Boll. Un. Mat. Ital. (6), A5(1986) 409–412.
Hooley, On the greatest prime factor of p + a, Mathematika, 20 (1973) 135–143.
Henryk Iwaniec, On the Brun-Tichmarsh theorem and related questions, Proc. Queen’s Number Theory Conf., Kingston, Ont. 1979, Queen’s Papers Pure Appl. Math., 54(1980) 67–78; Zbl. 446. 10036.
V. L. Klee, On a conjecture of Carmichael, Bull. Amer. Math. Soc., 53(1947) 1183–1186; MR 9, 269.
P. Masai and A. Valette, A lower bound for a counterexample to Carmichael’s
conjecture, Boll. Un. Mat. Ital. A (6), 1 (1982) 313–316; MR 84b:10008.
Carl Pomerance, On Carmichael’s conjecture, Proc. Amer. Math. Soc., 43 (1974) 297–298.
Carl Pomerance, Popular values of Euler’s function, Mathematika, 27 (1980) 84–89; MR 81k: 10076.
Aaron Schlafly and Stan Wagon, Carmichael’s conjecture on the Euler function is valid below 1010’000’0w, Math. Comput., 63(1994) 415–419; MR 94i: 1 1008.
M. V. Subbarao and L.-W. Yip, Carmichael’s conjecture and some analogues, in Théorie des Nombres (Québec, 1987), de Gruyter, Berlin—New York, 1989, 928–941 (and see Canad. Math. Bull., 34 (1991) 401–404.
Alain Valette, Fonction d’Euler et conjecture de Carmichael, Math. et Pédag., Bruxelles, 32 (1981) 13–18.
Stan Wagon, Carmichael’s `Empirical Theorem’, Math. Intelligencer, 8(1986) 61–63; MR 87d: 1 1012.
R. Wooldridge, Values taken many times by Euler’s phi-function, Proc. Amer. Math. Soc., 76(1979) 229–234; MR 80g: 10008.
P. Erdös, On the integers relatively prime to n and on a number-theoretic function considered by Jacobsthal, Math. Scand, 10(1962) 163–170; MR 26 #3651.
R. R. Hall and P. Shiu, The distribution of totatives, Cand. Math. Bull., 45(2002); MR 2003a: 11005.
Hooley, On the difference of consecutive numbers prime to n, Acta Arith, 8(1962/63) 343–347; MR 27 #5741.
L. Montgomery and R. C. Vaughan, On the distribution of reduced residues, Ann. of Math. (2), 123(1986) 311–333; MR 87g: 1 1119.
R. C. Vaughan, Some applications of Montgomery’s sieve, J. Number Theory, 5 (1973) 64–79.
R. C. Vaughan, On the order of magnitude of Jacobsthal’s function, Proc. Edinburgh Math. Soc.(2), 20(1976/77) 329–331; MR 56 #11937.
Krassimir T. Atanassov, New integer functions, related to 0 and a functions, Bull. Number Theory Related Topics, 11(1987) 3–26; MR 90j:11007.
P. A. Catlin, Concerning the iterated 0-function, Amer. Math. Monthly, 77(1970) 60–61.
P. Erdös, A. Granville, C. Pomerance and C. Spiro, On the normal behavior of the iterates of some arithmetic functions, in Berndt, Diamond, Halberstam and Hildebrand (editors) Analytic Number Theory, Proc. Conf. in honor P.T. Bateman, Allerton Park, 1989, Birkhäuser, Boston, 1990, 165–204; MR 92a: 1 1113.
P. Erdös, Some remarks on the iterates of the and a functions, Colloq. Math, 17(1967) 195–202; MR 36 #2573.
Paul Erdös and R. R. Hall, Euler’s 0-function and its iterates, Mathematika, 24(1977) 173–177; MR 57 #12356.
Miriam Hausman, The solution of a special arithmetic equation, Canad. Math. Bull., 25(1982) 114–117.
Douglas E. Iannucci, Deng Moujie and Graeme L. Cohen, On perfect totient numbers, preprint, 2003.
H. Maier, On the third iterates of the 0- and a-functions, Colloq. Math., 49(1984) 123–130; MR 86d:11006.
W. H. Mills, Iteration of the 0-function, Amer. Math. Monthly 50(1943) 547549; MR 5, 90.
A. Nicol, Some diophantine equations involving arithmetic functions, J. Math. Anal. Appl., 15(1966) 154–161.
Ivan Niven, The iteration of certain arithmetic functions, Canad. J. Math., 2(1950) 406–408; MR 12, 318.
S. S. Pillai, On a function connected with 0(n), Bull. Amer. Math. Soc., 35(1929) 837–841.
Carl Pomerance, On the composition of the arithmetic functions a and 0, Colloq. Math., 58(1989) 11–15; MR 91c:11003.
Harold N. Shapiro, An arithmetic function arising from the 0-function, Amer. Math. Monthly 50(1943) 18–30; MR 4, 188.
Charles R. Wall, Unbounded sequences of Euler-Dedekind means, Amer. Math. Monthly 92(1985) 587.
Richard Warlimont, On the iterates of Euler’s function, Arch. Math. (Basel), 76(2001) 345–349; MR 2002k:11167.
U. Balakrishnan, Some remarks on a(ç(n)), Fibonacci Quart., 32(1994) 293296; MR 95j:11091.
Cao Fen-Jin, The composite number-theoretic function a(0(n)) and its relation to n, Fujian Shifan Daxue Xuebao Ziran Kexue Ban, 10(1994) 31–37; MR 96c: 1 1008.
Graeme L. Cohem, On a conjecture of Makowski and Schinzel, Colloq. Math., 74(1997) 1–8; MR 98e:11006.
P. Erdds, Problem P. 294, Canad. Math. Bull., 23 (1980) 505.
Kevin Ford and Sergei Konyagin, On two conjectures of Sierpinski concerning the arithmetic functions a and 0, Number Theory in Progress, Vol. 2 (ZakopaneKoicielisko, 1997) 795–803, de Gruyter, Berlin, 1999; MR 2000d: 11120.
Kevin Ford, Sergei Konyagin and Carl Pomerance, Residue classes free of values of Euler’s function, Number Theory in Progress, Vol. 2 (Zakopane-Koicielisko, 1997) 805–812, de Gruyter, Berlin, 1999; MR 2000f: 11120.
Solomon W. Golomb, Equality among number–theoretic functions, preprint, Oct 1992; Abstract 882–11–16, Abstracts Amer. Math. Soc., 14 (1993) 415 – 416.
Grytczuk, F. Luca and M. Wôjtowicz, A conjecture of Erdös concerning inequalities for the Euler totient function, Publ. Math. Debrecen, 59(2001) 9–16; MR 2002f: 11005.
Grytczuk, F. Luca and M. Wôjtowicz, Some results on a(0(n)), Indian J. Math., 43(2001) 263–275; MR 2002k:11166.
Richard K. Guy, Divisors and desires, Amer. Math. Monthly, 104(1997) 359360.
Pentti Haukkanen, On an inequality for a(n)0(n), Octogon Math. Mag., 4(1996) 3–5.
Lin Da-Zheng and Zhang Ming-Zhi, On the divisibility relation ni(4.(n)+a(n)), Sichuan Daxue Xuebao, 34(1997) 121–123; MR 98d:11010.
Makowski and A. Schinzel, On the functions 0(n) and a(n), Colloq. Math, 13(1964–65) 95–99; MR 30 #3870.
Carl Pomerance, On the composition of the arithmetic functions a and 0, Colloq. Math., 58(1989) 11–15; MR 91c:11003.
Jôzsef Sândor, On Dedekind’s arithmetical function, Seminarul de Teoria Structurilor, Univ. Timisoara, 51(1988) 1–15.
Jôzsef Sândor, On the composition of some arithmetic functions, Studia Univ. Babeq-Bolyai Math., 34(1989) 7–14; MR 91i:11008.
Jôzsef Sândor and R. Sivaramakrishnan, The many facets of Euler’s totient. III. An assortment of miscellaneous topics, Nieuw Arch. Wisk., 11(1993) 97–130; MR 94i: 1 1007.
Robert C. Vaughan and Kevin L. Weis, On sigma-phi numbers, Mathematika, 48(2001) 169–189 (2003).
Zhang Ming-Zhi, A divisibility problem (Chinese), Sichuan Daxue Xuebao, 32(1995) 240–242; MR 97g: 1 1003.
Carlitz, A note on the left factorial function, Math. Balkanika, 5 (1975) 37–42.
Goran Gogié, Kurepa’s hypothesis on the left factorial (Serbian), Zb. Rad. Mat. Inst. Beograd. (N.S.) 5 (13) (1993) 41–45.
Aleksandar Ivié and Zarko Mijajlovié, On Kurepa’s problems in number theory, Duro Kurepa memorial volume, Publ. Inst. Math. (Beograd) (N.S.) 57(71)(1995) 19–28; MR 97a: 1 1007.
Winfried Kohnen, A remark on the left-factorial hypothesis, Univ. Beograd. Publ. Elektrotehn. Fak. Ser. Mat., 9(1998) 51–53; MR 99m: 1 1005.
D uro Kurepa, On some new left factorial propositions, Math. Balkanika, 4(1974) 383–386; MR 58 #10716.
Mijajlovié, On some formulas involving !n and the verification of the !n-hypothesis by use of computers, Publ. Inst. Math. (Beograd) (N.S.) 47(61)(1990) 24–32; MR 92d: 1 1134.
Alexandar Petojevié, On Kurepa’s hypothesis for the left factorial, Filomat No. 12, part 1 (1998) 29–37.
Zoran Sami, On generalization of functions n! and !n, Publ. Inst. Math. (Beograd)(N.S.) 60(74)(1996) 5–14; MR 98a: 1 1006.
Zoran Sami, A sequence un,, and Kurepa’s hypothesis on left factorial, Sympos. dedicated to memory of Duro Kurepa, Belgrade 1996, Sci. Rev. Ser. Sci. Eng., 19–20(1996) 105–113; MR 98b: 1 1016.
V. S. Vladimirov, Left factorials, Bernoulli numbers, and the Kurepa conjecture, Publ. Inst. Math. Beograd (N.S.), 72 (86) (2002) 11–22.
V. I. Arnold, Bernoulli-Euler updown numbers associated with function singularities, their combinatorics and arithmetics, Duke Math. J., 63(1991) 537–555; MR 93b: 58020.
V. I. Arnold, Snake calculus and the combinatorics of the Bernoulli, Euler and Springer numbers of Coxeter groups, Uspekhi Mat. Nauk, 47(1992) 3–45; transl. in Russian Math. Surveys, 47(1992) 1–51; MR 93h: 20042.
Lehmer, On congruences involving Bernoulli numbers and the quotients of Fermat and Wilson, Annals of Math. 39(1938) 350–360; Zbl. 19, 5.
Barry J. Powell, Advanced problem 6325, Amer. Math. Monthly 87 (1980) 826.
P. Erdös and Carl Pomerance, On the largest prime factors of n and n + 1, Aequationes Math, 17(1978) 311–321; MR 58 #476.
Mabkhout, Minoration de P(x 4 + 1), Rend. Sem. Fac. Sci. Univ. Cagliari, 63(1993) 135–148; MR 96e: 1 1039.
Schinzel, On primitive prime factors of an–b, Proc. Cambridge Philos. Soc., 58 (1962) 555–562.
Sun Qi and Zhang Ming-Zhi, Pairs where 2a — 2b divides na — nb for all n, Proc. Amer. Math. Soc., 93(1985) 218–220; MR 86c: 1 1004.
Marian Vâjâitu and Alexandru Zaharescu, A finiteness theorem for a class of exponential congruences, Proc. Amer. Math. Soc, 127(1999) 2225–2232; MR 99j:11003.
David Borwein and Jonathan M. Borwein, On an intriguing integral and some series related to ((4), Proc. Amer. Math. Soc, 123(1995) 1191–1198; MR 95e:11137.
Patrick Costello, A new largest Smith number, Fibonacci Quart., 40 (2002) 369–371.
Patrick Costello and Kathy Lewis, Lots of Smiths, Math. Mag, 75(2002) 223226.
Stephen K. Doig, Math Whiz makes digital discovery, The Miami Herald, 1986–08–22; Coll. Math. J., 18 (1987) 80.
Editorial, Smith numbers ring a bell? Fort Lauderdale Sun Sentinel, 86–09–16, p. 8A.
Editorial, Start with 4,937,775, New York Times, 86–09–02.
Kathy Lewis, Smith numbers: an infinite subset of N, M.S. thesis, Eastern Kentucky Univ., 1994.
Wayne L. McDaniel, The existence of infinitely many k-Smith numbers, Fibonacci Quart., 25 (1987) 76–80.
Wayne L. McDaniel, Powerful k-Smith numbers, Fibonacci Quart., 25 (1987) 225–228.
Wayne L. McDaniel, Palindromic Smith numbers, J. Recreational Math., 19 (1987) 34–37.
Wayne L. McDaniel, Difference of the digital sums of an integer base b and its prime factors, J. Number Theory, 31(1989) 91–98; MR 90e: 1 1021.
Wayne L. McDaniel and Samuel Yates, The sum of digits function and its application to a generalization of the Smith number problem, Nieuw Arch. Wisk.(4), 7 (1989) 39–51.
Sham Oltikar and Keith Wayland, Construction of Smith numbers, Math. Mag., 56 (1983) 36–37.
Ivars Peterson, In search of special Smiths, Science News, 86–08–16, p. 105. Michael Smith, Cousins of Smith numbers: Monica and Suzanne sets, Fibonacci Quart., 34(1996) 102–104; MR 97a: 1 1020.
Wilansky, Smith numbers, Two-Year Coll. Math. J., 13 (1982) 21.
Brad Wilson, For b 3 there exist infinitely many base b k-Smith numbers, Rocky Mountain J. Math., 29(1999) 1531–1535; MR 2000k: 11014.
Samuel Yates, Special sets of Smith numbers, Math. Mag., 59(1986) 293–296. Samuel Yates, Smith numbers congruent to 4 (mod 9), J. Recreational Math., 19 (1987) 139–141.
Samuel Yates, How odd the Smiths are, J. Recreational Math, 19(1987) 168174.
Samuel Yates, Digital sum sets, in R. A. Mollin (ed.), Number Theory, Proc. 1st Canad. Number Theory Assoc. Conf., Banff, 1988, de Gruyter, New York, 1990, pp. 627–634; MR 92c: 11008.
Samuel Yates, Tracking titanics, in R. K. Guy and R. E. Woodrow (eds.), The Lighter Side of Mathematics, Proc. Strens Mem. Conf., Calgary, 1986, Spectrum Series, Math. Assoc. of America, Washington DC, 1994.
P. Erdös and C. Pomerance, On the largest prime factors of n and n + 1, Aequationes Math, 17(1978) 311–321; MR 58 #476.
Nelson, D. E. Penney and C. Pomerance, “714 and 715”, J. Recreational Math., 7 (1994) 87–89.
Pomerance, Ruth-Aaron numbers revisited, Paul Erdôs and his mathematics, I (Budapest 1999 ) 567–579, Bolyai Soc. Math. Stud., 11, Janos Bolyai Math. Soc., Budapest, 2002.
David Wells, The Penguin Dictionary of Curious and Interesting Numbers, Penguin 1986, pp. 159–160.
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Guy, R.K. (2004). Divisibility. In: Unsolved Problems in Number Theory. Problem Books in Mathematics, vol 1. Springer, New York, NY. https://doi.org/10.1007/978-0-387-26677-0_3
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