Minimal non-neighborhood-perfect graphs
نویسندگان
چکیده
Neighborhood-perfect graphs form a subclass of the perfect graphs if the Strong Perfect Graph Conjecture of C. Berge is true. However, they are still not shown to be perfect. Here we propose the characterization of neighborhood-perfect graphs by studying minimal non-neighborhood-perfect graphs (MNNPG). After presenting some properties of MNNPGs, w e show that the only MNNPGs with neighborhood independence number one are the 3-sun and K. Also two further classes of neighborhood-perfect graphs are presented: line-graphs of bipartite graphs and a zfree cographs.
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ورودعنوان ژورنال:
- Journal of Graph Theory
دوره 21 شماره
صفحات -
تاریخ انتشار 1996