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Erdős problem 647

Let τ(n)\tau(n) count the number of divisors of nn. Is there some n>24n > 24 such that max⁡m<n(m+τ(m))≤n+2? \max_{m < n}(m + \tau(m)) \leq n + 2?

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4 retained statements36c6d0fef71a

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FormalConjectures/ErdosProblems/

647.lean

Retained formal statement3 of 4

Erdős says 'it is extremely doubtful' that there are infinitely many such nn, and in fact suggests that limn→∞max⁡m<n(τ(m)+m−n)=∞. lim_{n\to\infty} \max_{m < n}(\tau(m) + m − n) = \infty.

FormalConjectures/ErdosProblems/647.leanErdos647.erdos_647.variants.lim1 lineExact file
sorry ↔ Filter.Tendsto (fun n => ⨆ m, (ArithmeticFunction.sigma 0) ↑m + ↑m - n) Filter.atTop Filter.atTop
OpenStatement only, no proof