Digraphs with large exponent
نویسندگان
چکیده
Primitive digraphs on n vertices with exponents at least b!n=2c + 2, where !n = (n 1) + 1, are considered. For n 3, all such digraphs containing a Hamilton cycle are characterized; and for n 6, all such digraphs containing a cycle of length n 1 are characterized. Each eigenvalue of any stochastic matrix having a digraph in one of these two classes is proved to be geometrically simple.
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