A note on domination and total domination in prisms
نویسندگان
چکیده
Recently, Azarija et al. considered the prism G K2 of a graph G and showed that γt(G K2) = 2γ(G) if G is bipartite, where γt(G) and γ(G) are the total domination number and the domination number of G. In this note, we give a simple proof and observe that there are similar results for other pairs of parameters. We also answer a question from that paper and show that for all graphs γt(G K2) ≥ 4 3γ(G), and this bound is tight.
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ورودعنوان ژورنال:
- J. Comb. Optim.
دوره 35 شماره
صفحات -
تاریخ انتشار 2018