Research notes on every problem, and a library of the papers behind them. Built from the open erdos repository.
Updated
Claim. Let be the primes, with the convention , under which lies in and counts; the formal-conjectures statement adopts the same convention. If and every prime dividing is or , then ; so are the only such , and Problem 1058 is answered affirmatively: there are only finitely many. This is the Theorem of F. Luca, On a conjecture of Erdős and Stewart, Math. Comp. 70 (2001), no. 234, 893–896, received 1999-01-04 and published electronically 2000-03-08, the date this page carries; the source card is luca_2001_conjecture_erdos_stewart. The conjecture it proves is the one Guy reports as Erdős and Stewart's in Problem A2 of Unsolved problems in number theory.
Method. A -adic lower bound for linear forms in two logarithms (Bugeaud–Laurent), applied to , gives (so ); a computer search over cubic residues modulo the primes with forces and in any remaining solution, which the Erdős–Obláth theorem on excludes; a second computation disposes of . No independent check of the proof is recorded.
Acceptance. The paper is refereed: Math. Comp. 70 (2001), no. 234. The
site's curator, Thomas Bloom, marks Problem 1058 proved and credits Luca's
paper. The formal-conjectures statement for Problem 1058 is closed by sorry
but carries a formal-proof attribute pointing at the Lean 4 file linked above,
which declares itself a formalization of Luca's solution (informal author
Florian Luca; formal authors recorded as the AI systems Codex and GPT-5.6 Sol)
and proves that is a solution exactly when . That file
is linked as the claimant's formalization; this corpus has not built or audited
it, so it is not listed as formalized evidence.
Depends on. No other wiki page; the claim rests on the cited paper.