Bicritical domination and duality coalescence of graphs
نویسندگان
چکیده
A graph is bicritical if the removal of any pair of vertices decreases the domination number. We study properties of bicritical graphs and their relation with critical graphs. Next we obtain results for bicritical graphs with edge connectivity two or three. We also generalize the notion of the coalescence of two graphs, and we investigate the bicriticality of such graphs.
منابع مشابه
Bicritical total domination
A graph G with no isolated vertex is total domination bicritical if the removal of any pair of vertices, whose removal does not produce an isolated vertex, decreases the total domination number. In this paper we study properties of total domination bicritical graphs, and give several characterizations.
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