A tight bound on the set chromatic number
نویسندگان
چکیده
The purpose of this note is to provide a tight bound on the set chromatic number of a graph in terms of its chromatic number. Namely, for all graphs G, we show that χs(G) > dlog2 χ(G)e+ 1, where χs(G) and χ(G) are the set chromatic number and the chromatic number of G, respectively. This answers in the affirmative a conjecture of Gera, Okamoto, Rasmussen and Zhang.
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عنوان ژورنال:
- Discussiones Mathematicae Graph Theory
دوره 33 شماره
صفحات -
تاریخ انتشار 2013