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Erdős problem 950

This function was considered by de Bruijn, Erdős, and Turán, who showed that ∑n<xf(n)∼∑n<xf(n)2∼x\sum_{n<x}f(n)\sim \sum_{n<x}f(n)^2\sim x. They gave no proofs, but a proof of the (harder) second claim is given by Gorodetsky here [mathoverflow/508491].

Sources

The source's own material, retained exactly.

7 retained statements36c6d0fef71a

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FormalConjectures/ErdosProblems/

950.lean

Retained formal statement5 of 7

The study of f(p)f(p) is even harder, and Erdős could not prove that ∑p<xf(p)2∼π(x)\sum_{p<x}f(p)^2\sim \pi(x).

FormalConjectures/ErdosProblems/950.leanErdos950.erdos_950.variants.sum_primes3 linesExact file
True ↔  Asymptotics.IsEquivalent Filter.atTop (fun x => ∑ p ∈ Finset.range x with Prime p, Erdos950.f p ^ 2) fun x =>    ↑x.primeCounting
OpenStatement only, no proof