I'm looking for composite $n$ such that $$\sigma(n)\equiv n+1\pmod{\varphi(n)}$$
Are there only finitely many? Can this be proved?
This is Sloane's A070037 but there's not much information in the entry.
2026-03-30 17:01:52.1774890112
Composite $n$ such that $\sigma(n) \equiv n+1 \pmod{\phi(n)}$
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