T-coloring
In graph theory, a T-Coloring of a graph , given the set T of nonnegative integers containing 0, is a function that maps each vertex to a positive integer (color) such that if u and w are adjacent then . In simple words, the absolute value of the difference between two colors of adjacent vertices must not belong to fixed set T. The concept was introduced by William K. Hale. If T = {0} it reduces to common vertex coloring. The T-chromatic number, is the minimum number of colors that can be used in a T-coloring of G. The complementary coloring of T-coloring c, denoted is defined for each vertex v of G by where s is the largest color assigned to a vertex of G by the c function. (Wikipedia).
