English

G\'al-type GCD sums beyond the critical line

Number Theory 2016-04-12 v2

Abstract

We prove that k,=1N(nk,n)2α(nkn)αN22α(logN)b(α) \sum_{k,{\ell}=1}^N\frac{(n_k,n_{\ell})^{2\alpha}}{(n_k n_{\ell})^{\alpha}} \ll N^{2-2\alpha} (\log N)^{b(\alpha)} holds for arbitrary integers 1n1<<nN1\le n_1<\cdots < n_N and 0<α<1/20<\alpha<1/2 and show by an example that this bound is optimal, up to the precise value of the exponent b(α)b(\alpha). This estimate complements recent results for 1/2α11/2\le \alpha \le 1 and shows that there is no "trace" of the functional equation for the Riemann zeta function in estimates for such GCD sums when 0<α<1/20<\alpha<1/2.

Keywords

Cite

@article{arxiv.1512.03758,
  title  = {G\'al-type GCD sums beyond the critical line},
  author = {Andriy Bondarenko and Titus Hilberdink and Kristian Seip},
  journal= {arXiv preprint arXiv:1512.03758},
  year   = {2016}
}

Comments

A few minor misprints have been removed