Reinforcement numbers of digraphs
نویسندگان
چکیده
The reinforcement number of a graph G is the minimum cardinality of a set of extra edges whose addition results in a graph with domination number less than the domination number of G. In this paper we consider this parameter for digraphs, investigate the relationship between reinforcement numbers of undirected graphs and digraphs, and obtain further results for regular graphs. We also determine the exact values of the reinforcement numbers of de Bruijn digraphs and Kautz digraphs. © 2009 Elsevier B.V. All rights reserved.
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ورودعنوان ژورنال:
- Discrete Applied Mathematics
دوره 157 شماره
صفحات -
تاریخ انتشار 2009