Erdős problem 946
There are infinitely many such that . Proved in [He84]. Here τ is the divisor counting function, which is σ 0 in mathlib.
Sources
FormalConjectures/ErdosProblems/
946.lean
Retained formal statement
Improved lower bound in [Hi85]: .
(fun x => x / Real.log (Real.log x) ^ 3) =O[Filter.atTop] Erdos946.erdos946CountSolvedStatement only, no proof