Pre-hull number and lexicographic product
نویسنده
چکیده
Recently the invariant (copoint) pre-hull number ph(G) of a graph G that measures the nonconvexity of a convex space was introduced by Polat and Sabidussi in [18]. We introduce a similar invariant called convex pre-hull number which is a natural upper bound for the copoint pre-hull number and consider in this work both on the lexicographic product of graphs. We present exact values with respect to properties of the factors.
منابع مشابه
Pre-hull number of Cartesian and strong graph products
Recently introduced invariants copoint pre-hull number and convex pre-hull number are both numerical measures of nonconvexity of a graph G that is a convex space. We consider in this work both on the Cartesian and the strong product of graphs. Exact values in terms of invariants of the factors are presented for the first mentioned product. For strong product it is shown that such a result does ...
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