English

Extreme values of the Dedekind $\Psi$ function

Number Theory 2011-08-25 v2

Abstract

Let Ψ(n):=npn(1+1p)\Psi(n):=n\prod_{p | n}(1+\frac{1}{p}) denote the Dedekind Ψ\Psi function. Define, for n3,n\ge 3, the ratio R(n):=Ψ(n)nloglogn.R(n):=\frac{\Psi(n)}{n\log\log n}. We prove unconditionally that R(n)<eγR(n)< e^\gamma for n31.n\ge 31. Let Nn=2...pnN_n=2...p_n be the primorial of order n.n. We prove that the statement R(Nn)>eγζ(2)R(N_n)>\frac{e^\gamma}{\zeta(2)} for n3n\ge 3 is equivalent to the Riemann Hypothesis.

Keywords

Cite

@article{arxiv.1011.1825,
  title  = {Extreme values of the Dedekind $\Psi$ function},
  author = {Patrick Solé and Michel Planat},
  journal= {arXiv preprint arXiv:1011.1825},
  year   = {2011}
}

Comments

5 pages, to appear in Journal of Combinatorics and Number theory

R2 v1 2026-06-21T16:40:35.275Z