Domination dot-critical graphs with no critical vertices
نویسندگان
چکیده
A graph G is dot-critical if contracting any edge decreases the domination number. It is totally dot-critical if identifying any two vertices decreases the domination number. Burton and Sumner [Discrete Math. 306 (2006) 11–18] posed the problem: Is it true that for k 4, there exists a totally k-dot-critical graph with no critical vertices? In this paper, we show that this problem has a positive answer. © 2007 Elsevier B.V. All rights reserved.
منابع مشابه
The connectivity of domination dot-critical graphs with no critical vertices
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ورودعنوان ژورنال:
- Discrete Mathematics
دوره 308 شماره
صفحات -
تاریخ انتشار 2008