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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. Every simple cubic bipartite graph on at most 5858 vertices contains a cycle of length 44, 88 or 1616, so a cubic bipartite counterexample to the conjecture of Problem 64 has at least 6060 vertices, a cubic bipartite graph having even order; the abstract says this improves the published bound for the class from 3030 to 6060. The result is Julius Tranquilli, A 60-Vertex Lower Bound for Cubic Bipartite Counterexamples to the Erdős-Gyárfás Conjecture, arXiv:2608.02675, posted 2026-08-02 (the claim's date; nineteen pages). The abstract describes the proof: below 6262 vertices a cubic bipartite graph without 44- and 88-cycles contains a 66-cycle by a Moore-bound observation; the graph is the Levi graph of a linear symmetric v3v_3-configuration, in which that 66-cycle is a Berge triangle with, up to symmetry, two rooted extensions; a restricted-growth search on at most 2929 points exhausts both trees, and the computation is checked by two separately implemented exact procedures and a static witness certificate, with source code and certificates in an accompanying repository and Zenodo archive. Read depth: the arXiv record and abstract; the proof was not read and the certificates were not replayed. A thread post of 31 August 2026 cites the paper by title and number and reports an exhaustive search of its own reaching 6262 vertices, with AI assistance as the poster discloses; the post is not a dated manuscript and gets no page.

Covers. The statement of Problem 64 for cubic bipartite graphs on at most 5858 vertices, where the cycle found has length 222^2, 232^3 or 242^4; cubic graphs that are not bipartite are covered only up to 2929 vertices, by Markström's search (claim page), and bipartite graphs with a vertex of degree above 33 only up to 3131 vertices, by Salehi Nowbandegani and Esfandiari (claim page).

Depends on. No page of this wiki.

Standing. Claimed: an arXiv preprint with no refereed version or outside review known to this corpus; the computation is author-reported and has not been replayed here. The site labels the problem FALSIFIABLE and its commentary does not credit the paper.