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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. There is a constant crc_r, depending only on rr, such that for n>crkn>c_rk

f(n;r,k)=(nr)−(n−k+1r),f(n;r,k)=\binom nr-\binom{n-k+1}{r},

the number of rr-subsets of an nn-set meeting a fixed (k−1)(k-1)-set, which is the covering term of the maximum in Problem 1020. The paper writes f(n;r,k)f(n;r,k) for the least number of edges forcing kk pairwise disjoint edges and g(n;r,k−1)g(n;r,k-1) for the covering count, and its single Theorem states f(n;r,k)=1+g(n;r,k−1)f(n;r,k)=1+g(n;r,k-1) for n>crkn>c_rk; the proof is an induction on kk that splits on the maximum degree, a small maximum degree forcing a large maximal set of disjoint edges and a vertex of large degree being deleted for the induction. The paper poses the conjecture for every nn, recalls the Erdős–Ko–Rado case k=2k=2 and the Erdős–Gallai formula for r=2r=2, and gives no value of crc_r. The paper is P. Erdős, A problem on independent rr-tuples, Ann. Univ. Sci. Budapest. Eötvös Sect. Math. 8 (1965), 93–95, carded at A problem on independent r-tuples.

Covers. The range n>crkn>c_rk with crc_r unspecified. Explicit ranges of the same kind are the claims on Bollobás, Daykin and Erdős 1976, Huang, Loh and Sudakov 2012, Frankl, Łuczak and Mieczkowska 2012, Frankl 2013 and Frankl and Kupavskii 2022.

Depends on. No page of this wiki.

Acceptance. Refereed: the paper appeared in the Annales of the Eötvös University's mathematics section in 1965; the record gives only the year, so the page is dated to its first day. The site labels the problem FALSIFIABLE, an open label, so its commentary, which credits this range to the paper as [Er65d], is not acceptance and no reviewed is listed. Nothing here rests on this project's own review.