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Claim. For every constant CC and every KK, every sufficiently large nn has some kk with K<k<nK<k<n and

ω(n−k)≥log⁡klog⁡log⁡k+C,\omega(n-k)\ge\frac{\log k}{\log\log k}+C,

so the stronger version of Problem 679, that infinitely many nn have ω(n−k)<log⁡k/log⁡log⁡k+O(1)\omega(n-k)<\log k/\log\log k+O(1) for all large k<nk<n, is false. The argument, posted by the forum user DottedCalculator: take a primorial p1⋯pjp_1\cdots p_j below nn and set k=n−p1⋯pjk=n-p_1\cdots p_j, so that ω(n−k)=j\omega(n-k)=j. When the primorial is the largest below nn, j=m−1j=m-1 and k<p1⋯pmk<p_1\cdots p_m, so log⁡k<ϑ(pm)=m(log⁡m+log⁡log⁡m−1+o(1))\log k<\vartheta(p_m)=m(\log m+\log\log m-1+o(1)) by the asymptotics of the mmth prime, which gives log⁡k/log⁡log⁡k≤m−(1+o(1)) m/log⁡m\log k/\log\log k\le m-(1+o(1))\,m/\log m and hence ω(n−k)−log⁡k/log⁡log⁡k→∞\omega(n-k)-\log k/\log\log k\to\infty with nn. The post takes the largest primorial below nn, so its kk can be small; the formalization takes the previous primorial, which makes kk at least the gap between consecutive primorials and so large. The site's remarks state the sharper form, that for all large nn some k<nk<n has $\omega(n-k)\ge\log k/\log\log k+c\log k/(\log\log k)^2$ for a constant c>0c>0, which follows from the same estimate.

Covers. The second question only. The first question, whether infinitely many nn have ω(n−k)<(1+ϵ)log⁡k/log⁡log⁡k\omega(n-k)<(1+\epsilon)\log k/\log\log k for all large k<nk<n, 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 pn=(1+o(1)) nlog⁡np_n=(1+o(1))\,n\log n for the nnth prime, implies that for all CC and KK, eventually in nn, some k<nk<n with k>Kk>K has ω(n−k)≥log⁡k/log⁡log⁡k+C\omega(n-k)\ge\log k/\log\log k+C; 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 pn=n(log⁡n+log⁡log⁡n−1+o(1))p_n=n(\log n+\log\log n-1+o(1)). 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.