Extension of Hereditary Classes with Substitutions Extension of Hereditary Classes with Substitutions
نویسنده
چکیده
Let G and H be graphs. A substitution of H in G instead of a vertex v 2 V (G) is the graph G(v ! H), which consists of disjoint union of H and G ? v with the additional edge-set fxy : x 2 V (H); y 2 N G (v)g. For a hereditary class of graphs P, the substitutional closure of P is deened as the class P consisting of all graphs which can be obtained from graphs in P by repeated substitutions. Let P be an arbitrary hereditary class for which a characterization in terms of forbidden induced subgraphs is known. We propose a method of constructing forbidden induced subgraphs for P .
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