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arXiv · 2404.09720

A stability result for almost perfect matchings

Mingyang Guo·Hongliang Lu
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Abstract

Let $n,k,s$ be three integers and $β$ be a sufficiently small positive number such that $k\geq 3$, $0<1/n\ll β\ll 1/k$ and $ks+k\leq n\leq (1+β)ks+k-2$. A $k$-graph is called non-trivial if it has no isolated vertex. In this paper, we determine the maximum number of edges in a non-trivial $k$-graph with $n$ vertices and matching number at most $s$. This result confirms a conjecture proposed by Frankl (On non-trivial families without a perfect matching, \emph{European J. Combin.}, \textbf{84} (2020), 103044) for the case when $s$ is sufficiently large.

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Mingyang Guo, Hongliang Lu. 2024-04-15. A stability result for almost perfect matchings. https://arxiv.org/abs/2404.09720

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