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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. For every r≥2r\ge2 and every n>r2(r−1)/4n>r^2(r-1)/4, every graph GG with nn vertices and m≥tr(n)m\ge t_r(n) edges has a clique on rr vertices whose degree sum is at least 2rm/n2rm/n. The claimed result is R. J. Faudree, Complete subgraphs with large degree sums, J. Graph Theory 16 (1992), no. 4, 327--334, DOI 10.1002/jgt.3190160406. The paper is unread; the statement above is the one the introduction of Bollobás and Nikiforov's paper (p. 2; card) and the site's commentary give: "Later Faudree [7] proved the conjecture for any r≥2r\ge2 and n>r2(r−1)/4n>r^2(r-1)/4." The publisher's abstract, as the Crossref record carries it, states the hypothesis as n≥k2(k−1)/4n\ge k^2(k-1)/4 and "m<t(n,k)m<t(n,k)" edges, the second a slip for m≥t(n,k)m\ge t(n,k), the direction the abstract's next sentence (the conclusion fails in general below t(n,k)t(n,k)) and the Bollobás--Nikiforov account give; it is recorded as printed. This proves the corrected Statement of Problem 904 on that range of nn.

Covers. Every r≥2r\ge2 and every n>r2(r−1)/4n>r^2(r-1)/4, with m≥tr(n)m\ge t_r(n). The whole statement is the accepted full claim Bollobás--Nikiforov.

Depends on. Nothing in this wiki; the result rests on the cited paper alone.

Acceptance. Refereed: the Journal of Graph Theory, 16 (1992), no. 4. Reviewed: the site's curator, T. F. Bloom, credits Faudree with this range in the problem's commentary on a page labeled PROVED (LEAN), and Bollobás and Nikiforov's refereed paper credits it in its introduction.

Dating. The page is dated by the issue month, September 1992; the day is a placeholder.