On the Total Domination Number of Cartesian Products of Graphs
نویسندگان
چکیده
Let γ {k} t (G) denote the total {k}-domination number of graph G, and let G H denote the Cartesian product of graphs G and H . In this paper, we show that for any graphs G and H without isolated vertices, γ {k} t (G)γ {k} t (H) ≤ k(k + 1)γ {k} t (G H). As a corollary of this result, we have γt (G)γt (H) ≤ 2γt (G H) for all graphs G and H without isolated vertices, which is given by Pak Tung Ho (Util. Math., 2008, to appear) and first appeared as a conjecture proposed by Henning and Rall (Graph. Comb. 21:63–69, 2005).
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ورودعنوان ژورنال:
- Graphs and Combinatorics
دوره 21 شماره
صفحات -
تاریخ انتشار 2005