Ervin Győri , Binlong Li , Nika Salia , Casey Tompkins , Kitti Varga , Manran Zhu
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引用次数: 0
摘要
Bollobás证明了对于每一个k和r,使得k z + r包含一个偶数,一个n顶点的图,不包含长度为r modk的循环,最多只能包含一个线性数的边。这种图中最大边数的精确(或渐近)值对于很少的对(r和k)是已知的。在这项工作中,我们精确地确定了不包含长度为0mod4的循环的图中的最大边数。
Bollobás proved that for every k and ℓ such that contains an even number, an n-vertex graph containing no cycle of length can contain at most a linear number of edges. The precise (or asymptotic) value of the maximum number of edges in such a graph is known for very few pairs ℓ and k. In this work we precisely determine the maximum number of edges in a graph containing no cycle of length .
期刊介绍:
The Journal of Combinatorial Theory publishes original mathematical research dealing with theoretical and physical aspects of the study of finite and discrete structures in all branches of science. Series B is concerned primarily with graph theory and matroid theory and is a valuable tool for mathematicians and computer scientists.