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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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12 retained statements36c6d0fef71a

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FormalConjectures/ErdosProblems/

349.lean

Retained formal statement12 of 12

**The pair (1,2)(1, 2) is good.** The powers of two ⌊1⋅2n⌋=2n\lfloor 1\cdot 2^n\rfloor = 2^n form an additively complete set: every k≥1k \ge 1 is a finite sum of distinct powers of two.

FormalConjectures/ErdosProblems/349.leanErdos349.one_two_isGoodPair1 lineExact file
Erdos349.IsGoodPair 1 2
SolvedProof has a holeformal conjecturesexternal proof

The proof uses `sorry`: part of the argument is written but not proved. Lean accepts the file; it does not accept the theorem.