OPEN
This is open, and cannot be resolved with a finite computation.
Let\[V'(x)=\#\{\phi(m) : 1\leq m\leq x\}\]and\[V(x)=\#\{\phi(m) \leq x : 1\leq m\}.\]Does $\lim V(x)/V'(x)$ exist? Is it $>1$?
It is trivial that $V'(x) \leq V(x)$. In
[Er98] Erdős suggests the limit may be infinite. See also
[416].
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T. F. Bloom, Erdős Problem #417, https://www.erdosproblems.com/417, accessed 2026-01-16