On the Fractional Covering Number of Hypergraphs
نویسندگان
چکیده
The fractional covering number r* of a hypergraph H (V, E) is defined to be the minimum possible value of ,, v t(x) where ranges over all functions t: V which satisfy ,xe t(x) >= for all edges e e E. In the case of ordinary graphs G, it is known that 2r*(G) is always an integer. By contrast, it is shown (among other things) that for any rational p/q >= 1, there is a 3-uniform hypergraph H with-*(H) p/q.
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ورودعنوان ژورنال:
- SIAM J. Discrete Math.
دوره 1 شماره
صفحات -
تاریخ انتشار 1988