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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 preprint A Near-Optimal Linear Range for the Erdős Matching Conjecture by Mengyu Cao, Hong Liu and Haixiang Zhang, arXiv:2608.19118 (posted 2026-08-19, revised 2026-09-07), states that for every fixed k≥2k\ge2 there is s0(k)s_0(k) such that, whenever s≥s0(k)s\ge s_0(k) and n≥(k+1)sn\ge(k+1)s, every family of kk-subsets of an nn-set with matching number at most ss has at most (nk)−(n−sk)\binom nk-\binom{n-s}{k} members, with equality only for the family of kk-sets meeting a fixed ss-set; for k≥5k\ge5 the abstract gives the coefficient k+0.6k+0.6 in place of k+1k+1. In the notation of Problem 1020, with rr for the uniformity and k−1k-1 for the matching number, for every fixed r≥3r\ge3 there is s0(r)s_0(r) such that

f(n;r,k)=(nr)−(n−k+1r)(k−1≥s0(r), n≥(r+1)(k−1)),f(n;r,k)=\binom nr-\binom{n-k+1}{r} \qquad(k-1\ge s_0(r),\ n\ge(r+1)(k-1)),

the conjectured value in that range. Since the covering term is the larger exactly from about n=(r+1)kn=(r+1)k on, this is close to the whole range of the conjecture's second term for large kk. The abstract describes a stability theorem and probabilistic rigidity arguments. A reader posted the preprint on the site's discussion thread on 2026-08-20.

Covers. Every fixed r≥3r\ge3 for k−1≥s0(r)k-1\ge s_0(r) and n≥(r+1)(k−1)n\ge(r+1)(k-1), lowering the coefficient 53\tfrac53 of Frankl and Kupavskii 2022 to 1+1/r1+1/r. It says nothing about small kk or about the clique range.

Depends on. No page of this wiki.

Standing. Claimed. The preprint is not refereed, no proof claim was registered on the site's proof-claims tab, and the site's label and commentary, last edited on 28 December 2025, do not mention it. The proof is not verified by this corpus.