On the sizes of the graphs G, Gr, Gr \ G: the directed case
نویسندگان
چکیده
Let G be a directed graph and G be its r-th power. We study different issues dealing with the number of arcs, or size, of G and G: given the order and diameter of a strongly connected digraph, what is its maximum size, and which are the graphs achieving this bound? What is the minimum size of the r-th power of a strongly connected digraph, and which are the graphs achieving this bound? Given all strongly connected digraphs G of order n such that G = Kn, what is the minimum number of arcs that are added when going from G to G, and which are the graphs achieving this bound?
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ورودعنوان ژورنال:
- Australasian J. Combinatorics
دوره 48 شماره
صفحات -
تاریخ انتشار 2010