Minimum size transversals in uniform hypergraphs
نویسندگان
چکیده
منابع مشابه
Transversals in 4-Uniform Hypergraphs
Let H be a 4-uniform hypergraph on n vertices. The transversal number τ(H) of H is the minimum number of vertices that intersect every edge. The result in [J. Combin. Theory Ser. B 50 (1990), 129–133] by Lai and Chang implies that τ(H) 6 7n/18 when H is 3-regular. The main result in [Combinatorica 27 (2007), 473–487] by Thomassé and Yeo implies an improved bound of τ(H) 6 8n/21. We provide a fu...
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Let f(r; p; t) (p¿ t¿1, r¿2) be the maximum of the cardinality of a minimum transversal over all r-uniform hypergraphs H possessing the property that every subhypergraph of H with p edges has a transversal of size t. The values of f(r; p; 2) for p=3; 4; 5; 6 were found in Erdős et al. (Siberian Adv. Math. 2 (1992) 82–88). We give bounds on f(r; 7; 2), partially answering a question in Erdős et ...
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 2013
ISSN: 0012-365X
DOI: 10.1016/j.disc.2013.08.022