English

On multiplicative functions which are small on average

Number Theory 2017-06-12 v5

Abstract

Let ff be a completely multiplicative function that assumes values inside the unit disc. We show that if n<xf(n)x/(logx)A\sum_{n<x} f(n) \ll x/(\log x)^A, x>2x>2, for some A>2A>2, then either f(p)f(p) is small on average or ff pretends to be μ(n)nit\mu(n)n^{it} for some tt.

Keywords

Cite

@article{arxiv.1111.2659,
  title  = {On multiplicative functions which are small on average},
  author = {Dimitris Koukoulopoulos},
  journal= {arXiv preprint arXiv:1111.2659},
  year   = {2017}
}

Comments

51 pages. Slightly strengthened Theorem 1.2 and simplified its statement. Removed Remark 1.3. Other minor changes and corrections. To appear in Geom. Funct. Anal

R2 v1 2026-06-21T19:34:31.381Z