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Vertex criticality for upper domination and irredundance

✍ Scribed by P. J. P. Grobler; C. M. Mynhardt


Publisher
John Wiley and Sons
Year
2001
Tongue
English
Weight
104 KB
Volume
37
Category
Article
ISSN
0364-9024

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✦ Synopsis


Abstract

Let Ο€ be any of the domination parameters ir Ξ³, i, Ξ², Ξ“ or IR. The graph G is π‐critical (Ο€^+^‐critical) if the removal of any vertex of G causes Ο€(G) to decrease (increase). We show that the classes of IR‐critical and Γ‐critical graphs coincide, and exhibit a class of Ξ“^+^‐critical graphs. Β© 2001 John Wiley & Sons, Inc. J Graph Theory 37: 205–212, 2001


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