On the Odd Cycles of Normal Graphs
نویسندگان
چکیده
A graph is normal if there exists a cross-intersecting pair of set families one of which consists of cliques while the other one consists of stable sets, and furthermore every vertex is obtained as one of these intersections. It is known that perfect graphs are normal while Cs, CT. and (_: are not. We conjecture that these three graphs are the only minimally not normal graphs. We give sufficient conditions for a graph to be normal and WC characterize those normal graphs that are triangle-free.
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عنوان ژورنال:
- Discrete Applied Mathematics
دوره 94 شماره
صفحات -
تاریخ انتشار 1999