English

Note on the mean value of the Erd\H{o}s--Hooley Delta-function

Number Theory 2025-02-14 v9

Abstract

For integer n1n\geqslant 1 and real uu, let Δ(n,u):={d:dn,eu<deu+1}\Delta(n,u):=|\{d:d\mid n,\,{\rm e}^u<d\leqslant {\rm e}^{u+1}\}|. The Erd\H{o}s--Hooley Delta-function is then defined by Δ(n):=maxuRΔ(n,u).\Delta(n):=\max_{u\in{\mathbb R}}\Delta(n,u). We improve a recent upper bound for the mean value of this function by showing that, for large xx, we have nxΔ(n)x(log2x)5/2.\sum_{n\leqslant x}\Delta(n)\ll x(\log_2x)^{ 5/2}.

Keywords

Cite

@article{arxiv.2309.03958,
  title  = {Note on the mean value of the Erd\H{o}s--Hooley Delta-function},
  author = {Régis de la Bretèche and Gérald Tenenbaum},
  journal= {arXiv preprint arXiv:2309.03958},
  year   = {2025}
}