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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 Towards the Erdős matching conjecture for 4-uniform hypergraphs: stability and applications by Peter Frankl, Hongliang Lu, Jie Ma and Yuze Wu, arXiv:2602.19230 (posted 2026-02-22, revised 2026-06-10), states that the maximum number of edges of an nn-vertex 44-uniform hypergraph without s+1s+1 pairwise disjoint edges is max⁡{(n4)−(n−s4),(4s+34)}\max\{\binom n4-\binom{n-s}{4},\binom{4s+3}{4}\} whenever n≥5sn\ge5s and nn is sufficiently large. In the notation of Problem 1020, with k=s+1k=s+1,

f(n;4,k)=max⁡((4k−14),(n4)−(n−k+14))(n≥5(k−1), n≥n0).f(n;4,k)=\max\left(\binom{4k-1}{4},\binom n4-\binom{n-k+1}{4}\right) \qquad(n\ge5(k-1),\ n\ge n_0).

The abstract describes a stability result of independent interest, applied to minimum-degree thresholds for matchings in 55- and 66-uniform hypergraphs. A reader posted the preprint on the site's discussion thread on 2026-02-24.

Covers. The case r=4r=4 for n≥5(k−1)n\ge5(k-1) with nn large. The rest of the case r=4r=4 is the subject of the later claims on Hou, Hu and Liu 2026, for k≥6005k\ge6005 and n≥4kn\ge4k, and Babanskyy 2026, for every k≥2k\ge2 and n≥4kn\ge4k.

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.