A lower bound for the CO-irredundance number of a graph
نویسنده
چکیده
This paper establishes a necessary and sufficient condition for a CO-irredundant set of vertices of a graph to be maximal and shows that the smallest cardinality of a maximal CO-irredundant set in an n vertex graph with maximum degree is bounded below by n/2 for = 2, 4n/13 for = 3 and 2n/(3 − 3) for 4. This result is best possible and extremal graphs are characterised for 3. © 2005 Elsevier B.V. All rights reserved.
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عنوان ژورنال:
- Discrete Mathematics
دوره 295 شماره
صفحات -
تاریخ انتشار 2005