Moore Graphs and Cycles Are Extremal Graphs for Convex Cycles
نویسندگان
چکیده
منابع مشابه
Moore Graphs and Cycles Are Extremal Graphs for Convex Cycles
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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ژورنال
عنوان ژورنال: Journal of Graph Theory
سال: 2014
ISSN: 0364-9024
DOI: 10.1002/jgt.21837