Strong Oriented Chromatic Number of Planar Graphs without Short Cycles
نویسندگان
چکیده
Let M be an additive abelian group. An M-strong-oriented coloring of an oriented graph G is a mapping φ from V (G) to M such that φ(u) 6= φ(v) whenever −→uv is an arc in G and φ(v)−φ(u) 6= −(φ(t)−φ(z)) whenever −→uv and zt are two arcs in G. The strong oriented chromatic number of an oriented graph is the minimal order of a group M such that G has an M-strong-oriented coloring. This notion was introduced by Nešetřil and Raspaud [Ann. Inst. Fourier, 49(3):1037-1056, 1999].
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عنوان ژورنال:
- Discrete Mathematics & Theoretical Computer Science
دوره 10 شماره
صفحات -
تاریخ انتشار 2008