Kourovka Problem 19.25 - Totient Sums and Simplicity
Prior state unknown→disproved
Do a finite group's order together with $\sum_{g \in G} \varphi(|g|)$ determine whether the group is simple? A simple and a non-simple group of order $6048$ share the statistic $23984$.
SourceReplayReproducedFormal proofStatement auditExternal checkExpert reviewPeer review