منابع مشابه
The local exponent sets of primitive digraphsø
Let D = (V ,E) be a primitive digraph. The local exponent of D at a vertex u ∈ V , denoted by exp D (u), is defined to be the least integer k such that there is a directed walk of length k from u to v for each v ∈ V . Let V = {1, 2, . . ., n}. The vertices of V can be ordered so that exp D (1) 6 exp D (2) 6 · · · 6 exp D (n) = γ (D). We define the kth local exponent set En(k) := {expD(k) | D ∈ ...
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ژورنال
عنوان ژورنال: Linear Algebra and its Applications
سال: 2016
ISSN: 0024-3795
DOI: 10.1016/j.laa.2015.08.009