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Erdős problem 650

Let f(m)f(m) be such that if A⊆{1,…,N}A\subseteq \{1,\ldots,N\} has ∣A∣=m\lvert A\rvert=m then every interval in [1,∞)[1,\infty) of length 2N2N contains ≥f(m)\geq f(m) many distinct integers b1,…,brb_1,\ldots,b_r where each bib_i is divisible by some ai∈Aa_i\in A, where a1,…,ara_1,\ldots,a_r are distinct.

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The source's own material, retained exactly.

4 retained statements36c6d0fef71a

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FormalConjectures/ErdosProblems/

650.lean

Retained formal statement4 of 4

Erdős and Surányi [ErSu59] proved that f(m)≥mf(m)\geq\sqrt{m}.

FormalConjectures/ErdosProblems/650.leanErdos650.erdos_650.variants.erdos_suranyi1 lineExact file
∀ (m : ℕ), √↑m ≤ ↑(Erdos650.f m)
SolvedStatement only, no proof