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Erdős problem 1210

Let A⊆[1,n)A\subseteq [1,n) be a set of integers such that (a,b)=1(a,b)=1 for all distinct a,b∈Aa,b\in A. Is it true that ∑a∈A1n−a≤∑p<n1p+O(1)\sum_{a\in A}\frac{1}{n-a}\leq \sum_{p < n}\frac{1}{p}+O(1)?

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2 retained statements36c6d0fef71a

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FormalConjectures/ErdosProblems/

1210.lean

Retained formal statement2 of 2

In [Er80] he claims he "did not state this quite correctly" in [Er77c]. The problem in [Er77c] which Erdős is presumably referring to states that if n<q1<⋯<qk≤mn < q_1 < \cdots < q_k\leq m is the set of primes in (n,m](n,m] then ∑1qi−n<∑p<m−n1p+O(1)\sum \frac{1}{q_i-n} < \sum_{p < m-n}\frac{1}{p}+O(1).

FormalConjectures/ErdosProblems/1210.leanErdos1210.erdos_1210.variants.er80_correction4 linesExact file
True ↔  ∃ C,    ∀ (n m : ℕ),      n < m → ∑ q ∈ Finset.Ioc n m with Prime q, 1 / (↑q - ↑n) < ∑ p ∈ Finset.range (m - n) with Prime p, 1 / ↑p + C
OpenStatement only, no proof