Erdős Problem #277

Is it true that, for every $c$, there exists an $n$ such that $\sigma(n)>cn$ but there is no covering system whose moduli all divide $n$?

#277: [Er77c][ErGr80,p.27][Er82e]

number theory | covering systems

This was answered affirmatively by Haight [Ha79].

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This page was last edited 06 October 2025.

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