Article
Keywords:
$k$-subdomination number of a graph; three-dimensional cube graph
Summary:
One of numerical invariants concerning domination in graphs is the $k$-subdomination number $\gamma ^{-11}_{kS}(G)$ of a graph $G$. A conjecture concerning it was expressed by J. H. Hattingh, namely that for any connected graph $G$ with $n$ vertices and any $k$ with $\frac{1}{2} n < k \leqq n$ the inequality $\gamma ^{-11}_{kS}(G) \leqq 2k - n$ holds. This paper presents a simple counterexample which disproves this conjecture. This counterexample is the graph of the three-dimensional cube and $k=5$.
References:
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MR 1415993
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Majority domination and its generalizations. In: Domination in Graphs. Advanced Topics, T. W. Haynes, S. T. Hedetniemi, P. J. Slater (eds.), Marcel Dekker, Inc., New York-Basel-Hong Kong, 1998.
MR 1605689 |
Zbl 0891.05042