Erdős problem 946

There are infinitely many $n$ such that $τ(n) = τ(n+1)$ . Proved in [He84]. Here τ is the divisor counting function, which is `σ 0` in mathlib.

Sources

The source's own material, retained exactly.

5 retained statements36c6d0fef71a

FormalConjectures/ErdosProblems/

946.lean

Retained formal statement5 of 5

Upper bound in [EPS87]: $O(x / \sqrt{\log \log x})$ .

FormalConjectures/ErdosProblems/946.leanErdos946.erdos_946.variants.upper_bound1 lineExact file

1Erdos946.erdos946Count =O[Filter.atTop] fun x => x / √(Real.log (Real.log x))

SolvedStatement only, no proof