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Research notes on every problem, and a library of the papers behind them. Built from the open erdos repository.

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Claim. The formal-conjectures statement file for Problem 349 defines IsGoodPair t α as the additive completeness of the set of values ⌊tαn⌋\lfloor t\alpha^n\rfloor, n≥0n\ge0 (the range of the sequence, so a value occurring at several indices is available once), and carries six partial results tagged research solved, each with a formal_proof attribute pointing to a proof in the fork cepadugato/formal-conjectures (the formalization links, pinned to the commits the attributes name or to the proof branch's head of 2026-06-10): for t>0t>0 and α>2\alpha>2 the pair is not good; for t>0t>0 and 0<α≤10<\alpha\le1 the pair is not good; (1,2)(1,2) is good, since every natural number is a sum of distinct powers of two; (1/2k,2)(1/2^k,2) is good for every kk; for integers t≥2t\ge2 and any integer α\alpha the pair is not good, every subset sum being a multiple of tt; and, assembling these, for integers t,α≥1t,\alpha\ge1 the pair is good if and only if (t,α)=(1,2)(t,\alpha)=(1,2). The record link is the statement file at its last change (2026-09-18), which carries the attributes.

Covers. The formal statements are the site's wording, with values counted once and the index from n=0n=0, not the corrected Statement of Problem 349, which counts each term ⌊tαn⌋\lfloor t\alpha^n\rfloor, n≥1n\ge1, at most once even when values repeat. Every sum of distinct values is a sum of distinct terms, and the pair (t,α)(t,\alpha) with the index from n=0n=0 is the Statement's pair (t/α,α)(t/\alpha,\alpha), so the completeness of (1/2k,2)(1/2^k,2), k≥0k\ge0, gives the completeness of the Statement's pairs (1/2k,2)(1/2^k,2) with k≥1k\ge1. On those pairs completeness is proved, so the claim's value is proved. The non-completeness results do not carry over, since the Statement allows more sums: at α=1\alpha=1 the Statement's sequence is complete for 1≤t<21\le t<2, and its only complete positive integer pair is (1,1)(1,1). Those results answer the site's wording, not the corrected statement; for α>2\alpha>2 and 0<α<10<\alpha<1 the Statement's answer is Proposition 1 of van Doorn's paper (van Doorn's claim page). The proofs are elementary and settle nothing in 1<α<21<\alpha<2.

Claimant and postings. The proofs were contributed to the catalog under the GitHub account cepadugato in two pull requests, #4225 (opened 2026-06-10, merged 2026-06-16, the α>2\alpha>2 result) and #4233 (opened 2026-06-11, merged 2026-06-21, the other five), whose descriptions name no human author and end with the footer that they were generated with Claude Code, the contributor's own disclosure. The first description reports a build under Lean v4.27.0 with the axioms propext, Classical.choice and Quot.sound only. The proofs live in the fork rather than the catalog because they exceed the catalog's proof-length guideline, so the catalog file carries statements with sorry and the formal_proof pointers. The page is dated by the first pull request.

Standing. Claimed: the catalog's maintainers merged the statements, which is a review of the statements rather than an acceptance of the problem, and the site's page does not mention the results. This corpus has not built or audited the fork's proofs, so no formalized evidence is listed and the links are formalizations of the claimant's own result, not a warrant.

Depends on. Nothing in this wiki.