Acyclic orientations and chromatic generating functions
نویسندگان
چکیده
منابع مشابه
Acyclic orientations and chromatic generating functions
Let P (k) be the chromatic polynomial of a graph with n ≥ 2 vertices and no isolated vertices, and let R(k) = P (k + 1)/k(k + 1). We show that the coefficients of the polynomial (1 − t) ∑ ∞ k=1 R(k)t are nonnegative and we give a combinatorial interpretation to R(k) when k is a nonpositive integer.
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 2001
ISSN: 0012-365X
DOI: 10.1016/s0012-365x(00)00344-7