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Erdős problem 298

Does every set A⊆NA \subseteq \mathbb{N} of positive density contain some finite S⊂AS \subset A such that ∑n∈S1n=1\sum_{n \in S} \frac{1}{n} = 1?

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2 retained statements36c6d0fef71a

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FormalConjectures/ErdosProblems/

298.lean

Retained formal statement2 of 2

The literal natural-density interpretation of Erdős Problem 298 follows from [Bl21].

FormalConjectures/ErdosProblems/298.leanErdos298.erdos_298.variants.natural_density1 lineExact file
True ↔ ∀ (A : Set ℕ), 0 ∉ A → A.HasPosDensity → ∃ S, ↑S ⊆ A ∧ ∑ n ∈ S, 1 / ↑n = 1
SolvedStatement only, no proof