On the Caccetta-Häggkvist Conjecture
نویسنده
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.
منابع مشابه
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ورودعنوان ژورنال:
- Graphs and Combinatorics
دوره 18 شماره
صفحات -
تاریخ انتشار 2002