Claims

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2022_07_25_wigderson: The two-edge star and two-edge matching, both bipartite, have joint extremal number 1 while each alone has linear extremal number; an unpublished elementary note with no outside acceptance documented.

2026_08_01_openai: A finite family of connected bipartite graphs, each containing a cycle, with ex(n, F) = O(n^(4/3 - 1/48)) and ex(n, G) = Omega(n^(4/3)), G in F; the disproof the site accepted on 31 August 2026, with no refereed version.

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