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Erdős problem 349

For 0<α≤10 < \alpha \le 1 and any t>0t > 0, (t,α)(t, \alpha) is not a good pair: every term ⌊tαn⌋\lfloor t\alpha^n\rfloor lies in the finite interval [0,⌊t⌋][0, \lfloor t\rfloor] (since αn≤1\alpha^n \le 1), so every subset sum is bounded by the constant ∑i∈[0,⌊t⌋]i\sum_{i \in [0,\lfloor t\rfloor]} i, and no large integer can be a subset sum. A partial result on the open Erdős Problem 349, complementing the 2<α2 < \alpha and integer-coefficient cases.

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The source's own material, retained exactly.

12 retained statements36c6d0fef71a

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FormalConjectures/ErdosProblems/

349.lean

Retained formal statement9 of 12

For any kk there exists some tk∈(0,1)t_k\in (0,1) such that the set of α\alpha such that the sequence ⌊tkαn⌋\lfloor t_k\alpha^n\rfloor is complete consists of at least kk disjoint line segments.

FormalConjectures/ErdosProblems/349.leanErdos349.exists_t_for_k_disjoint_segments7 linesExact file
∀ (k : ℕ),  ∃ t ∈ Set.Ioo 0 1,    ∃ ι,      ↑k ≤ Set.univ.encard ∧        ∃ I,          (∀ (i : ι), 2 ≤ (I i).encard ∧ (I i).Nonempty ∧ IsConnected (I i)) ∧            Pairwise (Function.onFun Disjoint I) ∧ ⋃ i, I i ⊆ {α | α > 0 ∧ Erdos349.IsGoodPair t α}
SolvedStatement only, no proof