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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