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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. There is an absolute constant C>0C>0 such that infinitely many nn satisfy ω(n+k)≤Ck\omega(n+k)\le Ck for every integer k≥1k\ge1. This is Theorem 1.1 of the preprint, which proves the bound for Ω(n+k)\Omega(n+k), the number of prime factors counted with multiplicity, and hence for ω(n+k)≤Ω(n+k)\omega(n+k)\le\Omega(n+k). It answers the question of Problem 248 yes, with the implied constant in ω(n+k)≪k\omega(n+k)\ll k absolute. The proof runs a Maynard-type high-dimensional sieve whose dimension grows slowly and handles the shifts k≫log⁡log⁡nk\gg\log\log n inside the sieve weights rather than by counting bounds; the authors' forum announcement of 2025-12-01 explains that the shifts k=o(log⁡log⁡n)k=o(\log\log n) carry the difficulty. The source card is Tao and Teräväinen 2025.

Acceptance. The site's curator, Thomas F. Bloom, records in the problem's commentary (page last edited 2026-04-17) that the problem has been resolved by this result and labels the problem proved; that documented acceptance is the reviewed evidence. The preprint (arXiv:2512.01739, v1 of 2025-12-01, v2 of 2026-04-25) has no journal publication on record, so refereed is not listed. A Lean 4 development in the lean-proofs repository (file first published 2026-08-23) declares itself a formalization of a solution to the problem with Tao and Teräväinen as its informal authors and proves the same statement as Erdos248.erdos_248; its header credits the formal proof to the AI systems Codex and GPT-5.6 Sol and the repository to Boris Alexeev, and says that it implements the Tao–Teräväinen weighted-sieve argument directly for ω\omega. The formal-conjectures project links that file as the formal proof of its statement erdos_248 (category research solved), which is the Lean that the site's label refers to; the statement file is linked above as a record, since it holds no proof. This corpus has not built the development, printed its axioms or audited its statement, so formalized is not listed.

Later strengthening. Lau (arXiv:2604.15042, 2026-04-16) proves that for some absolute CC infinitely many nn have Ω(n+k)≤Clog⁡k\Omega(n+k)\le C\log k for every k≥2k\ge2, which the site records as an improvement of this bound; see Lau 2026. It refines the method of this claim, and after the shift n↦n+1n\mapsto n+1 it implies the problem's statement by itself, since ω(n+1+j)≤Ω(n+(j+1))≤Clog⁡(j+1)≤Cj\omega(n+1+j)\le\Omega(n+(j+1))\le C\log(j+1)\le Cj for every j≥1j\ge1; it is recorded as a second accepted claim on Lau 2026.

Depends on. Nothing in this wiki; the argument is self-contained in the preprint.