The Even Cycle Problem for Directed Graphs
نویسنده
چکیده
If each arc in a strongly connected directed graph of minimum in-degree and outdegree at least 3 is assigned a weight 0 or 1, then the resultingweighted directed graph has a directed cycle of even total weight. This provesa conjecture made by L. Lovasz in 1975 and has applications to colour-criticalhypergraphs, sign-nonsingular matrices, and permanents of matrices. MATHEMATICAL INSTITUTE, TECHNICAL UNIVERSITY OF DENMARK, DK-2800 LYNGBY,DENMARK License or copyright restrictions may apply to redistribution; see http://www.ams.org/journal-terms-of-use
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