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 such that infinitely many positive integers satisfy for every integer . This is Theorem 1.1 of Cheuk Fung (Joshua) Lau, On the number of prime factors of consecutive integers, arXiv:2604.15042 (v1 2026-04-16, v2 2026-06-24), stated for , the number of prime factors counted with multiplicity, and hence for . It answers the question of Problem 248 yes after a shift of : for such an put ; then for every ,
since for , so infinitely many have for all with an absolute implied constant. The paper's random models (Conjectures 5 and 6) say that the bound is sharp up to the constant. The proof refines the probabilistic sieve argument of Tao and Teräväinen: is drawn from weighted by a product of Selberg sieve weights with polynomially decaying levels , and a sieve-weighted concentration estimate for (Proposition 5.5) makes the union bound over converge. Theorem 1.3 gives the same bound for . The source card is Lau 2026.
Depends on. Nothing in this wiki; the argument is self-contained in the preprint. It refines the method of Tao and Teräväinen 2025 but does not rest on that result.
Acceptance. Reviewed: the site's curator, Thomas F. Bloom, labels the
problem PROVED (LEAN) and credits Lau [La26] in the problem's commentary with
improving the bound to for all , noting that
may be replaced by (page last edited 2026-04-17, after a
thread comment of the same day cited the preprint, which the site marks as
addressed); that documented acceptance is the reviewed evidence. Not
refereed: the preprint has no journal publication on record. Not formalized:
no Lean development of this result is known; the lean-proofs file linked from
the Tao–Teräväinen page formalizes their linear bound, not this one.