k-Subdomination in graphs

نویسندگان

  • Gerard J. Chang
  • Sheng-Chyang Liaw
  • Hong-Gwa Yeh
چکیده

For a positive integer k, a k-subdominating function of a graph G=(V; E) is a function f :V →{−1; 1} such that ∑u∈NG [v] f(u)¿ 1 for at least k vertices v of G. The ksubdomination number of G, denoted by ks(G), is the minimum of ∑ v∈V f(v) taken over all k-subdominating functions f of G. In this article, we prove a conjecture for k-subdomination on trees proposed by Cockayne and Mynhardt. We also give a lower bound for ks(G) in terms of the degree sequence of G. This generalizes some known results on the k-subdomination number ks(G), the signed domination number s(G) and the majority domination number maj(G). ? 2002 Elsevier Science B.V. All rights reserved.

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عنوان ژورنال:
  • Discrete Applied Mathematics

دوره 120  شماره 

صفحات  -

تاریخ انتشار 2002