Transversal numbers of uniform hypergraphs
نویسنده
چکیده
The transversal number ~(H) of a hypergraph H is the minimum eardinality of a set of vertices that intersects all edges of H. For k ~ 1 define ck = supz(H)/(ra + n), where H ranges over all k-uniform hypergraphs with n vertices and m edges. Applying probabilistic arguments we show that ck = (1 + o ( 1 ) ) ~ , r . This settles a problem of Tuza. t ~
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ورودعنوان ژورنال:
- Graphs and Combinatorics
دوره 6 شماره
صفحات -
تاریخ انتشار 1990