On a problem of Lewin
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Jian Shen; Stewart Neufeld
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Article
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1998
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Elsevier Science
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English
⚖ 864 KB
A digraph G is called primitive if for some positive integer k there is a walk of length exactly k from each vertex u to each vertex o (possibly u again). If G is primitive, the smallest such k is called the exponent of G, denoted by exp(G). In 1971, M. Lewin introduced the paramater 1(G) for a prim