Coloring directed cycles
نویسنده
چکیده
Sopena in his survey [E. Sopena, The oriented chromatic number of graphs: A short survey, preprint 2013] writes, without any proof, that an oriented cycle ~ C can be colored with three colors if and only if λ( ~ C) = 0, where λ( ~ C) is the number of forward arcs minus the number of backward arcs in ~ C. This is not true. In this paper we show that ~ C can be colored with three colors if and only if λ( ~ C) = 0 (mod 3) or ~ C does not contain three consecutive arcs going in the same direction.
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عنوان ژورنال:
- CoRR
دوره abs/1307.5186 شماره
صفحات -
تاریخ انتشار 2013