On the ratio of the domination number and the independent domination number in graphs
نویسندگان
چکیده
We let γ(G) and i(G) denote the domination number and the independent domination number ofG, respectively. Recently, Rad and Volkmann conjectured that i(G)/γ(G) ≤ ∆(G)/2 for every graph G, where ∆(G) is the maximum degree of G. In this note, we construct counterexamples of the conjecture for ∆(G) ≥ 6, and give a sharp upper bound of the ratio i(G)/γ(G) by using the maximum degree of G.
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ورودعنوان ژورنال:
- Discrete Applied Mathematics
دوره 178 شماره
صفحات -
تاریخ انتشار 2014