Induced matchings in intersection graphs

نویسنده

  • Kathie Cameron
چکیده

An induced matching in a graph G is a set of edges, no two of which meet a common node or are joined by an edge of G; that is, an induced matching is a matching which forms an induced subgraph. Induced matchings in graph G correspond precisely to independent sets of nodes in the square of the line-graph of G, which we denote by [L(G)]. Often, if G has a nice representation as an intersection graph, we can obtain a nice representation of [L(G)] as an intersection graph. Then, if the independent set problem is polytime-solvable in [L(G)], the induced matching problem is polytime-solvable in G. In particular, we show that if G is a polygon-circle graph, then so is [L(G)], and the same holds for asteroidal triple-free and interval-4lament graphs. It follows that the induced matching problem is polytime-solvable in these classes. Gavril’s interval-4lament graphs include cocomparability and polygon-circle graphs, and the latter include circle graphs, circular-arc graphs, chordal graphs, and outerplanar graphs. c © 2003 Published by Elsevier B.V. MSC: 05C70; 05C62; 05C85; 68R10

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عنوان ژورنال:
  • Electronic Notes in Discrete Mathematics

دوره 5  شماره 

صفحات  -

تاریخ انتشار 2000