Erdős problem 647
Let count the number of divisors of . Is there some such that
Sources
FormalConjectures/ErdosProblems/
647.lean
Retained formal statement
Erdős says 'it is extremely doubtful' that there are infinitely many such , and in fact suggests that
sorry ↔ Filter.Tendsto (fun n => ⨆ m, (ArithmeticFunction.sigma 0) ↑m + ↑m - n) Filter.atTop Filter.atTopOpenStatement only, no proof