Abstract
We provide examples of multiplicative functions f supported on the k-free integers such that at primes \(f(p)=\pm 1\) and such that the partial sums of f up to x are \(o(x^{1/k})\). Further, if we assume the Generalized Riemann Hypothesis, then we can improve the exponent 1/k: There are examples such that the partial sums up to x are \(o(x^{1/(k+\frac{1}{2})+\epsilon })\), for all \(\epsilon >0\). This generalizes to the k-free integers the results of Aymone (J. Number Theory, 212:113-121, 2020).
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Notes
We recall that \(\zeta \) stands for the classical Riemann zeta function and for a Dirichlet character \(\chi \), \(L(s,\chi )\) stands for the classical L-function \(L(s,\chi )=\sum _{n=1}^\infty \frac{\chi (n)}{n^s}\). The Riemann Hypothesis for \(\zeta \) states that all zeros \(\zeta (s_0)=0\) with real part \(Re(s_0)>0\) have real part equals 1/2. The Generalized Riemann Hypothesis is the same statement for \(L(s,\chi )\).
References
Apostol, T.M.: Introduction to Analytic Number Theory. Undergraduate Texts in Mathematics. Springer, New York (1976)
Aymone, M.: The Erdős discrepancy problem over the squarefree and cubefree integers. Mathematika 68, 51–73 (2022)
Aymone, M.: A note on multiplicative functions resembling the Möbius function. J. Number Theory 212, 113–121 (2020)
Basquin, J.: Sommes friables de fonctions multiplicatives aléatoires. Acta Arith. 152, 243–266 (2012)
Erdős, P.: Some unsolved problems. Magyar Tud. Akad. Mat. Kutató Int. Közl. 6, 221–254 (1961)
Granville, A., Soundararajan, K.: Pretentious multiplicative functions and an inequality for the zeta-function. In: Anatomy of Integers. CRM Proceedings of the Lecture Notes, vol. 46, pp. 191–197. American Mathematical Society, Providence, RI (2008)
Halász, G.: On random multiplicative functions. In: Hubert Delange Colloquium (Orsay,: vol. 83 of Publ. Math. Orsay. Univ. Paris XI, Orsay 1983, 74–96 (1982)
Harper, A.J.: Almost sure large fluctuations of random multiplicative functions, arXiv:2012.15809 (2021)
Harper, A.J.: Bounds on the suprema of Gaussian processes, and omega results for the sum of a random multiplicative function. Ann. Appl. Probab. 23, 584–616 (2013)
Harper, A.J.: On the limit distributions of some sums of a random multiplicative function. J. Reine Angew. Math. 678, 95–124 (2013)
Iwaniec, H., Kowalski, E.: Analytic Number Theory. American Mathematical Society Colloquium Publications, vol. 53. American Mathematical Society, Providence, RI (2004)
Lau, Y.-K., Tenenbaum, G., Wu, J.: On mean values of random multiplicative functions. Proc. Am. Math. Soc. 141, 409–420 (2013)
Montgomery H.L., Vaughan, R.C.: Multiplicative Number Theory. I. Classical Theory. Cambridge Studies in Advanced Mathematics, vol. 97. Cambridge University Press, Cambridge (2007)
Shiryaev, A.N.: Probability. Graduate Texts in Mathematics, 2nd edn, vol. 95, Springer, New York. Translated from the first (1980) Russian edition by R. P. Boas (1996)
Soundararajan, K.: Partial sums of the Möbius function. J. Reine Angew. Math. 631, 141–152 (2009)
Tao, T.: The Erdös Discrepancy Problem. Discrete Anal., pp. Paper No. 1, 29 (2016)
Tenenbaum, G.: Introduction to Analytic and Probabilistic Number Theory. Graduate Studies in Mathematics, American Mathematical Society, 3rd edn, vol. 163, Providence, RI. Translated from the 2008 French edition by Patrick D. F. Ion (2015)
Titchmarsh, E.C.: The Theory of the Riemann Zeta-Function, 2nd edn. The Clarendon Press Oxford University Press, New York. Edited and with a preface by D. R. Heath-Brown (1986)
Wintner, A.: Random factorizations and Riemann’s hypothesis. Duke Math. J. 11, 267–275 (1944)
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We would like to thank the anonymous referee for a careful reading of the paper and for useful suggestions that improved the exposition.
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Marco Aymone is supported by CNPq - Grant Universal Number 403037/2021-2; Caio Bueno was financed in part by the scholarship from Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil (CAPES) - Finance code 001; Kevin Medeiros was financed by the Fapemig scholarship.
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Aymone, M., Bueno, C. & Medeiros, K. Multiplicative functions supported on the k-free integers with small partial sums. Ramanujan J 59, 713–728 (2022). https://doi.org/10.1007/s11139-022-00618-9
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DOI: https://doi.org/10.1007/s11139-022-00618-9