Moore Graphs and Cycles Are Extremal Graphs for Convex Cycles
نویسندگان
چکیده
Let ρ(G) denote the number of convex cycles of a simple graph G of order n, size m, and girth 3 ≤ g ≤ n. It is proved that ρ(G) ≤ ng (m−n+ 1) and that equality holds if and only if G is an even cycle or a Moore graph. The equality also holds for a possible Moore graph of diameter 2 and degree 57 thus giving a new characterization of Moore graphs.
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عنوان ژورنال:
- Journal of Graph Theory
دوره 80 شماره
صفحات -
تاریخ انتشار 2015