Research notes on every problem, and a library of the papers behind them. Built from the open erdos repository.
Updated
Claim. For every constant and every , every sufficiently large has some with and
so the stronger version of Problem 679, that infinitely many have for all large , is false. The argument, posted by the forum user DottedCalculator: take a primorial below and set , so that . When the primorial is the largest below , and , so by the asymptotics of the th prime, which gives and hence with . The post takes the largest primorial below , so its can be small; the formalization takes the previous primorial, which makes at least the gap between consecutive primorials and so large. The site's remarks state the sharper form, that for all large some has $\omega(n-k)\ge\log k/\log\log k+c\log k/(\log\log k)^2$ for a constant , which follows from the same estimate.
Covers. The second question only. The first question, whether infinitely many have for all large , is untouched; the only result on it recorded here is the conditional one on [[problems/arithmetic_functions/E0679/claims/2026_04_16_lau|Lau's page]].
Depends on. Nothing in this wiki.
Lean. The gist linked above, posted in the thread on 2026-01-12 by the
forum user llllvvuu, is a Lean file whose author's note says it was given to
Aristotle together with DottedCalculator's proof and that Aristotle
formalized the proof of its Claim; as a formalization that names
DottedCalculator's proof as its source, it is a link on this page. Claim
states that pn_asymptotic, the assertion for the
th prime, implies that for all and , eventually in , some
with has ; the file proves it with no
sorry. The asymptotic it assumes is proved in the PNT+ project but not in
Mathlib. The pinned revision is the last of the four made that day; the
earlier ones assumed the stronger asymptotic
. This corpus has not built the file, so it
gives no formalized evidence.
Standing. Claimed. The site's remarks (page last edited 17 April 2026) credit DottedCalculator with disproving the stronger version, but the site labels the problem OPEN, so the remark is commentary and not acceptance. There is no refereed version.