The k-tuple domination number revisited
โ Scribed by Vadim Zverovich
- Publisher
- Elsevier Science
- Year
- 2008
- Tongue
- English
- Weight
- 183 KB
- Volume
- 21
- Category
- Article
- ISSN
- 0893-9659
No coin nor oath required. For personal study only.
โฆ Synopsis
The following fundamental result for the domination number ฮณ (G) of a graph G was proved by Alon and Spencer, Arnautov, Lovรกsz and Payan:
where n is the order and ฮด is the minimum degree of vertices of G. A similar upper bound for the double domination number was found by Harant and Henning [J. Harant, M.A. Henning, On double domination in graphs, Discuss. Math. Graph Theory 25 (2005) 29-34], and for the triple domination number by Rautenbach and Volkmann [D. Rautenbach, L. Volkmann, New bounds on the k-domination number and the k-tuple domination number, Appl. Math. Lett. 20 (2007) 98-102], who also posed the interesting conjecture on the k-tuple domination number: for any graph G with ฮด โฅ k -1,
where
/n is the m-degree of G. This conjecture, if true, would generalize all the mentioned upper bounds and improve an upper bound proved in [A. Gagarin, V. Zverovich, A generalised upper bound for the k-tuple domination number, Discrete Math. (2007), in press (
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