On the Chromatic Number of the Visibility Graph of a Set of Points in the Plane
نویسندگان
چکیده
The visibility graph V(P ) of a point set P ⊆ R has vertex set P , such that two points v, w ∈ P are adjacent whenever there is no other point in P on the line segment between v and w. We study the chromatic number of V(P ). We characterise the 2and 3-chromatic visibility graphs. It is an open problem whether the chromatic number of a visibility graph is bounded by its clique number. Our main result is a super-polynomial lower bound on the chromatic number (in terms of the clique number).
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ورودعنوان ژورنال:
- Discrete & Computational Geometry
دوره 34 شماره
صفحات -
تاریخ انتشار 2005