On the Caccetta-Häggkvist Conjecture

نویسنده

  • Jian Shen
چکیده

It was conjectured by Caccetta and Häggkvist in 1978 that every digraph G with n vertices and minimum outdegree at least r contains a directed cycle of length at most dn=re. By refining an argument of Chvátal and Szemerédi, we prove that such G contains a directed cycle of length at most n=r þ 73.

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عنوان ژورنال:
  • Graphs and Combinatorics

دوره 18  شماره 

صفحات  -

تاریخ انتشار 2002