Defective Coloring of Toroidal Graphs and Graphs ofBounded
نویسندگان
چکیده
A graph is (k; d)-colorable if one can color the vertices with k colors such that no vertex is adjacent to more than d vertices of the same color. In this paper we investigate the existence of such colorings in surfaces. It is shown that a toroidal graph is (3; 2)and (5; 1)colorable, and that a graph of genus is ( =(d + 1) + 4; d)-colorable, where is the maximum chromatic number of a graph embeddable on the surface of genus .
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