New bounds on the size of nearly perfect matchings in almost regular hypergraphs
نویسندگان
چکیده
Let H $H$ be a k $k$ -uniform D $D$ -regular simple hypergraph on N $N$ vertices. Based an analysis of the Rödl nibble, in 1997, Alon, Kim and Spencer proved that if ⩾ 3 $k \geqslant 3$ , then contains matching covering all but at most − 1 / ( ) + o $ND^{-1/(k-1)+o(1)}$ vertices, asked whether this bound is tight. In paper we improve their by showing for > η $ND^{-1/(k-1)-\eta }$ vertices some = Θ 0 $\eta \Theta (k^{-3}) 0$ when are sufficiently large. Our approach consists nibble process not only constructs large it also produces many well-distributed ‘augmenting stars’ which can used to significantly constructed process. this, results Kostochka from 1998 Vu 2000 size matchings almost regular hypergraphs with small codegree. As consequence, best known bounds combinatorial designs general parameters. Finally, Molloy Reed chromatic index codegree (which applied Steiner triple systems more designs).
منابع مشابه
Nearly perfect matchings in regular simple hypergraphs
For every fixed k ≥ 3 there exists a constant ck with the following property. Let H be a kuniform, D-regular hypergraph on N vertices, in which no two edges contain more than one common vertex. If k > 3 then H contains a matching covering all vertices but at most ckND. If k = 3, then H contains a matching covering all vertices but at most c3ND lnD. This improves previous estimates and implies, ...
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ژورنال
عنوان ژورنال: Journal of the London Mathematical Society
سال: 2023
ISSN: ['1469-7750', '0024-6107']
DOI: https://doi.org/10.1112/jlms.12792