On the Convexity Number of Graphs
نویسندگان
چکیده
A set of vertices S in a graph is convex if it contains all vertices which belong to shortest paths between vertices in S. The convexity number c(G) of a graph G is the maximum cardinality of a convex set of vertices which does not contain all vertices of G. We prove NP-completeness of the problem to decide for a given bipartite graph G and an integer k whether c(G) ≥ k. Furthermore, we identify natural necessary extension properties of graphs of small convexity number and study the interplay between these properties and upper bounds on the convexity number.
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ورودعنوان ژورنال:
- Graphs and Combinatorics
دوره 28 شماره
صفحات -
تاریخ انتشار 2012