منابع مشابه
Chromatic polynomials of some nanostars
Let G be a simple graph and (G,) denotes the number of proper vertex colourings of G with at most colours, which is for a fixed graph G , a polynomial in , which is called the chromatic polynomial of G . Using the chromatic polynomial of some specific graphs, we obtain the chromatic polynomials of some nanostars.
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This paper describes an improvement in the upper bound for the magnitude of a coefficient of a term in the chromatic polynomial of a general graph. If ar is the coefficient of the q r term in the chromatic polynomial P (G, q), where q is the number of colors, then we find ar ≤ ( e v−r ) − ( e−g+2 v−r−g+2 ) + ( e−kg−g+2 v−r−g+2 ) − ∑kg−lg n=1 ∑lg−1 m=1 ( e−g+1−n−m v−r−g ) − δg,3 ∑kg+l ∗ g+1 −lg ...
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ژورنال
عنوان ژورنال: Journal of Combinatorial Theory, Series B
سال: 1972
ISSN: 0095-8956
DOI: 10.1016/0095-8956(72)90003-2