Notes on Fractional k-Covered Graphs
نویسندگان
چکیده
A graph G is fractional k-covered if for each edge e of G, there exists a fractional k-factor h, such that h(e) = 1. If k = 2, then a fractional k-covered graph is called a fractional 2-covered graph. The binding number bind(G) is defined as follows, bind(G) = min{ |NG(X)| |X| : Ø = X ⊆ V (G), NG(X) = V (G)}. In this paper, it is proved that G is fractional 2-covered if δ(G) ≥ 4 and bind(G) > 5 3 . Keywords—graph, binding number, fractional k-factor, fractional k-covered graph.
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