Erdős problem 828

Is it true that, for any $a \in \mathbb{Z}$ , there are infinitely many $n$ such that $\phi(n) | n + a$ ?

Sources

The source's own material, retained exactly.

3 retained statements36c6d0fef71a

FormalConjectures/ErdosProblems/

828.lean

Retained formal statement2 of 3

When $n > 1$ , Lehmer conjectured that $\phi(n) | n - 1$ if and only if $n$ is prime.

FormalConjectures/ErdosProblems/828.leanErdos828.erdos_828.variants.lehmer_conjecture1 lineExact file

1True ↔ ∀ n > 1, n.totient ∣ n - 1 ↔ Prime n

OpenStatement only, no proof