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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. The wording of Problem 1077 is false. Fix 0<α<130<\alpha<\tfrac13 and let GG be a clique on k=⌈2 n(1+α)/2⌉+1k=\lceil\sqrt2\,n^{(1+\alpha)/2}\rceil+1 vertices together with nn vertices in all, the rest isolated; then GG has k(k−1)/2>n1+αk(k-1)/2>n^{1+\alpha} edges. The comment itself takes a clique on slightly more than n(1+α)/2n^{(1+\alpha)/2} vertices and says that it has more than n1+αn^{1+\alpha} edges; that size gives only about n1+α/2n^{1+\alpha}/2 edges, and the factor 2\sqrt2 here repairs the count without changing the argument. A DD-balanced subgraph with an edge lies inside the clique, since a vertex of degree zero beside an edge breaks the balance condition, and the clique has fewer than n1−αn^{1-\alpha} vertices for large nn because (1+α)/2<1−α(1+\alpha)/2<1-\alpha; so no DD-balanced subgraph on more than n1−αn^{1-\alpha} vertices has an edge, for every ϵ>0\epsilon>0, every DD and every large nn. A second comment of 30 December 2025 says, without argument, that putting the other vertices on a path still refutes the question. The reason, this page's own deduction and not the comment's: a DD-balanced subgraph with a vertex on the path has minimum degree at most 22, so at most DD times its vertex count in edges, below ϵm1+α\epsilon m^{1+\alpha} for large mm, while one inside the clique has too few vertices as before. Both comments are Boris Alexeev's, and Alexeev credits both examples to Aristotle. Since the question quantifies over every ϵ,α>0\epsilon,\alpha>0, one α\alpha refutes it as a whole; the examples decide nothing about the question restricted to α≥13\alpha\ge\tfrac13, and the curator's guess at the intended question, with nαn^\alpha in place of n1−αn^{1-\alpha}, is a variant recorded in the problem page's Formulation.

Depends on. Nothing in this wiki; the count is elementary.

Standing. Claimed. The site's label DISPROVED (LEAN) and its commentary (last edited 8 January 2026) credit JunGao and the complete bipartite witness of the claim page JunGao, and its thanks line names Yael Dillies, JunGao and Zach Hunter; neither names this comment, Alexeev or Aristotle, so the site's acceptance does not cover this claim and the page lists no reviewed evidence. The curator's thread replies are discussion, not acceptance: on 25 December 2025 the curator guessed that the authors meant graphs without isolated vertices and asked for an expert's view, and on 31 December 2025, after the path variant, conceded the point and wrote that the exponent 1−α1-\alpha was a typo and that the intended question was the one JunGao answered. Not refereed: the examples exist only as forum comments. The problem page recomputes the complete bipartite witness and not this one; the count above is the comment's argument with its clique size corrected.