Research notes on every problem, and a library of the papers behind them. Built from the open erdos repository.
Updated
Claim. The wording of Problem 1077 is false. Fix and let be a clique on vertices together with vertices in all, the rest isolated; then has edges. The comment itself takes a clique on slightly more than vertices and says that it has more than edges; that size gives only about edges, and the factor here repairs the count without changing the argument. A -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 vertices for large because ; so no -balanced subgraph on more than vertices has an edge, for every , every and every large . 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 -balanced subgraph with a vertex on the path has minimum degree at most , so at most times its vertex count in edges, below for large , 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 , one refutes it as a whole; the examples decide nothing about the question restricted to , and the curator's guess at the intended question, with in place of , 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 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.