A Note on Directed 5-Cycles in Digraphs

Affiliation(s)

Department of Mathematics Southwestern University of Finance and Economics Chengdu 611130, China.

School of Mathematical Sciences University of Science and Technology of China Wentsun Wu Key Laboratory of CASHefei 230026, China.

Department of Mathematics Southwestern University of Finance and Economics Chengdu 611130, China.

School of Mathematical Sciences University of Science and Technology of China Wentsun Wu Key Laboratory of CASHefei 230026, China.

Abstract

In this note, it is proved that if*α*≥0.24817, then any digraph on *n* vertices with minimum outdegree at least *αn* contains a directed cycle of length at most 5.

In this note, it is proved that if

Cite this paper

H. Liang and J. Xu, "A Note on Directed 5-Cycles in Digraphs,"*Applied Mathematics*, Vol. 3 No. 7, 2012, pp. 805-808. doi: 10.4236/am.2012.37120.

H. Liang and J. Xu, "A Note on Directed 5-Cycles in Digraphs,"

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