The existence of uniquely −G colourable graphs

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The existence of uniquely -G colourable graphs

Given graphs F and G and a nonnegative integer k, a function n : V(F) ~ {1 . . . . . k} is a G k-colouring of F if no induced copy of G is monochromatic; F is G k-chromatic if F has a G k-colouring but no G (k 1)-colouring. Further, we say F is uniquely G k-colourable if F is G k-chromatic and, up to a permutation of colours, it has only one G k-colouring. Such notions are extensions of the wel...

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ژورنال

عنوان ژورنال: Discrete Mathematics

سال: 1998

ISSN: 0012-365X

DOI: 10.1016/s0012-365x(97)00022-8