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Nonderogatory unicyclic digraphs. (English) Zbl 1139.05026
Summary: A digraph is nonderogatory if its characteristic polynomial and minimal polynomial are equal. We find a characterization of nonderogatory unicyclic digraphs in terms of Hamiltonicity conditions. An immediate consequence of this characterization ia that the complete product of difans and diwheels is nonderogatory.

05C20Directed graphs (digraphs), tournaments
Full Text: DOI EuDML
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