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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. Write d(x)=max⁡pn<x(pn+1−pn)d(x)=\max_{p_n<x}(p_{n+1}-p_n), a maximum over the gaps whose left endpoint lies below xx, so that a gap counts even when its right endpoint lies beyond xx. For a fixed C>1C>1 let A(C)A(C) be the assertion that

π(y+Cd(x))−π(y)∼Cd(x)log⁡y\pi(y+Cd(x))-\pi(y)\sim\frac{Cd(x)}{\log y}

as x→∞x\to\infty, uniformly over x/2<y<xx/2<y<x; the question of Problem 1138 asks whether A(C)A(C) holds for every C>1C>1, and this is the reading the paper, the site and the Lean statement in google-deepmind/formal-conjectures take. Theorem 1.2 of the paper: if 1<C1<C21<C_1<C_2 and C2−C1<1/2C_2-C_1<1/2, then A(C1)A(C_1) and A(C2)A(C_2) cannot both hold. Corollary 3.1: A(C)A(C) fails for some C>1C>1, so the answer to the question is no.

The obstruction uses strict record gaps. Since prime gaps are unbounded, there are infinitely many indices nkn_k whose gap Dk=pnk+1−pnkD_k=p_{n_k+1}-p_{n_k} exceeds every earlier gap. Put xkx_k, yky_k and zkz_k inside that gap, with xkx_k above both yky_k and zkz_k and yk<zky_k<z_k chosen so that yk+C2Dk=zk+C1Dky_k+C_2D_k=z_k+C_1D_k; the record property gives d(xk)=Dkd(x_k)=D_k, and the positions give xk/2<yk<zk<xkx_k/2<y_k<z_k<x_k for large kk. The intervals (yk,yk+C2Dk](y_k,y_k+C_2D_k] and (zk,zk+C1Dk](z_k,z_k+C_1D_k] share their right endpoint, and neither (yk,zk](y_k,z_k] nor the gap below contains a prime, so both contain the same number of primes. If A(C1)A(C_1) and A(C2)A(C_2) both held, that common count would be asymptotic to C2Dk/log⁡ykC_2D_k/\log y_k and to C1Dk/log⁡zkC_1D_k/\log z_k at once; as zk/yk→1z_k/y_k\to 1, this forces C2/C1=1C_2/C_1=1, a contradiction. The site's remark records a shorter variant: with x=pn+1x=p_n+1 and y=pn−2dy=p_n-2d for a record gap d=pn+1−pnd=p_{n+1}-p_n, the counts for C=2C=2 and for any 2<C<32<C<3 coincide.

The disproof settles the question as posed, for every C>1C>1 at once. Whether A(C)A(C) fails for every single C>1C>1 is open: the obstruction rules out two constants close together, and the site's discussion notes that a lattice LZL\mathbb Z of surviving constants with L>1L>1 is not excluded (constants exactly 11 apart are ruled out as well: at a record gap dd their counts differ by one prime while the predicted main terms differ by d/log⁡yd/\log y, which tends to infinity); the behavior when CC grows slowly with xx is also open. Neither is part of this claim.

Acceptance. The site's curator, Thomas F. Bloom, marks Problem 1138 disproved and credits the result to Sunder, Kumrawat and Cheri together with GPT 5.5, the reviewed evidence. The paper is H. Sunder, S. Kumrawat and K. Cheri, An elementary obstruction to a uniform prime-gap asymptotic, dated April 2026 and posted on the second author's page; it was announced in the site's discussion on 25 April 2026, the date of this page. In that announcement the authors state that GPT-5.5 Pro and GPT-5.5 Thinking were used in developing and checking the argument; the paper itself names no AI system. The three human authors are the claimants here, with the system named as they name it. No journal publication is recorded, so no refereed evidence is listed.

Formalization. Three Lean developments formalize the disproof, each following the paper, so they are links on this page and not claims of their own. The first, posted in the site's discussion on 4 May 2026 by Lorenzo Luccioli and generated with Aristotle (Harmonic), pinned at the gist revision in the link, proves Theorem 1.2 and Corollary 3.1 for its own definitions. The second, 1138a.lean in Yan Yablonovskiy's fork of formal-conjectures, pinned at the commit of 22 June 2026, reuses the definitions of the formal-conjectures statement and proves erdos1138_corollary: the per-CC asymptotic, taken along the filter of x→∞x\to\infty with x/2<y<xx/2<y<x, cannot hold for every C>1C>1, with C=2C=2 and C=9/4C=9/4 as the contradicting pair; the formal_proof attribute of the statement in google-deepmind/formal-conjectures names this file, and its 504 lines contain no sorry, axiom or native_decide token. The third, Erdos1138.lean in Boris Alexeev's lean-proofs repository, added there on 6 May 2026 and pinned at its last change, of 25 August 2026, is a modified copy of the first; its header names Sunder, Kumrawat and Cheri as informal authors and Aristotle and Lorenzo Luccioli as formal authors and marks it unconditional. This corpus has built none of them, so no formalized evidence is listed, and the formal-conjectures statement file is not a formalization link.

Depends on. Nothing beyond the cited paper.