The Binding Number of Trees and K(1,3)-free Graphs
نویسنده
چکیده
The binding number of a graphG is defined to be the minimum of |N(S)|/|S| taken over all nonempty S ⊆ V (G) such that N(S) 6= V (G). In this paper another look is taken at the basic properties of the binding number. Several bounds are established, including ones linking the binding number of a tree to the “distribution” of its end-vertices. Further, it is established that under some simple conditions, K(1, 3)-free graphs have binding number equal to (p(G)− 1)/(p(G)− δ(G)) and applications of this are considered.
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تاریخ انتشار 2006