Addition to 'An upper bound  for the number of  odd multiperfect numbers'

P. Yuan; Z. Zhang

Addition to 'An upper bound for the number of odd multiperfect numbers'

Authors

P. Yuan South China Normal University
Z. Zhang

Abstract

A natural number

$n$ is called

$k$ -perfect if

$\sigma(n) = kn$ . In this note, we show that for any integers

$r\ge5$ , the number of odd

$k$ -perfect numbers

$n$ with

$k\ge2$ and

$\omega(n)\le r$ is bounded by

$\frac{4^{r^2}}{2^{r+2}(r-1)!}$ . 10.1017/S0004972713000452

Published

2013-12-02

Issue

Vol. 89 No. 1 (2014)

Section

Articles

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