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Symmetric Dyck Paths and Hooley’s \(\varDelta \)-Function

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Part of the book series: Lecture Notes in Computer Science ((LNTCS,volume 10432))

Abstract

Hooley [6] introduced the function

$$ \varDelta (n) := \max _{u \in \mathbb {R}}\# \left\{ d | n: \quad u < \log d \leqslant u+1 \right\} , $$

where \(\log \) is the natural logarithm. Changing the base of the logarithm from e to an arbitrary real number \(\lambda > 1\), we define

$$ \varDelta _{\lambda }(n) := \max _{u \in \mathbb {R}}\# \left\{ d | n:\quad u < \log _{\lambda } d \leqslant u+1 \right\} . $$

The aim of this paper is to express \(\varDelta _{\lambda }(n)\) as the height of a symmetric Dyck path defined in terms of the distribution of the divisors of n.

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Notes

  1. 1.

    Höft described his own research as follows (personal communication, March 24, 2017): “My work in this context has been to find formulas, develop Mathematica code to compute the sequences and their associated irregular triangles, and use those to computationally verify conjectures for initial segments of some sequences. In addition, I tried to find ‘elementary’ arguments for conjectures stated in OEIS about the ‘symmetric representation of sigma’ and to prove in special cases that the area defined by two adjacent Dyck paths actually equals sigma (thus justifying the phrase used in OEIS in those cases)”.

  2. 2.

    Let k be a field and \(\mathcal {R}\) be a k-algebra. The codimension of an ideal I of \(\mathcal {R}\) is the dimension of the quotient \(\mathcal {R}/I\) as a vector space over k.

  3. 3.

    The function \(\varDelta _2(n)\) was introduced by Erdös and Nicolas [2], using the notation F(n), before Hooley’s paper [6].

References

  1. Blondin-Massé, A., Brlek, S., Garon, A., Labbé, S.: Combinatorial properties of \(f\)-palindromes in the Thue-Morse sequence. Pure Math. Appl. 19(2–3), 39–52 (2008)

    MathSciNet  MATH  Google Scholar 

  2. Erdös, P., Nicolas, J.L.: Méthodes probabilistes et combinatoires en théorie des nombres. Bull. Sci. Math. 2, 301–320 (1976)

    MATH  Google Scholar 

  3. Fine, N.J.: Basic Hypergeometric Series and Applications, vol. 27. American Mathematical Soc., Providence (1988)

    MATH  Google Scholar 

  4. Hall, R.R., Tenenbaum, G.: Divisors. Cambridge Tracts in Mathematics, vol. 90. Cambridge University Press, Cambridge (1988).

    Google Scholar 

  5. Höft, H.F.W.: On the symmetric spectrum of odd divisors of a number. https://oeis.org/A241561/a241561.pdf

  6. Hooley, C.: On a new technique and its applications to the theory of numbers. Proc. London Math. Soc. 3(1), 115–151 (1979)

    Article  MathSciNet  MATH  Google Scholar 

  7. Kassel, C., Reutenauer, C.: Counting the ideals of given codimension of the algebra of Laurent polynomials in two variables. arXiv preprint arXiv:1505.07229 (2015)

  8. Kassel, C., Reutenauer, C.: Complete determination of the zeta function of the Hilbert scheme of \(n\) points on a two-dimensional torus. arXiv preprint arXiv:1610.07793 (2016)

  9. Rodríguez Caballero, J.M.: On a function introduced by Erdös and Nicolas (To appear)

    Google Scholar 

  10. Sloane, N.J.A., et al.: The on-line encyclopedia of integer sequences (2012)

    Google Scholar 

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Acknowledgement

The author thanks S. Brlek, C. Kassel and C. Reutenauer for they valuable comments and suggestions concerning this research. Also, the author want to express his gratitude to H. F. W. Höft for the useful exchanges of information.

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Correspondence to José Manuel Rodríguez Caballero .

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Rodríguez Caballero, J.M. (2017). Symmetric Dyck Paths and Hooley’s \(\varDelta \)-Function. In: Brlek, S., Dolce, F., Reutenauer, C., Vandomme, É. (eds) Combinatorics on Words. WORDS 2017. Lecture Notes in Computer Science(), vol 10432. Springer, Cham. https://doi.org/10.1007/978-3-319-66396-8_23

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  • DOI: https://doi.org/10.1007/978-3-319-66396-8_23

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  • Publisher Name: Springer, Cham

  • Print ISBN: 978-3-319-66395-1

  • Online ISBN: 978-3-319-66396-8

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