Circular Colouring the Plane
نویسندگان
چکیده
The unit distance graph R is the graph with vertex set R2 in which two vertices (points in the plane) are adjacent if and only if they are at Euclidean distance 1. We prove that the circular chromatic number of R is at least 4, thus “tightening” the known lower bound on the chromatic number of R.
منابع مشابه
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