Approximations for chromatic polynomials
نویسندگان
چکیده
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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Table of contents Introduction 1. Relation of the present work to previous researches on map-coloring and summary of results. 356 2. Definitions. 358 Chapter I. First principles in the numerical and theoretical treatment of chromatic polynomials 1. The three fundamental principles. 362 2. The quadrilateral reduction formula. 363 3. The pentagon reduction formula. 365 4. The m-gon reduction form...
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The chromatic polynomials of certain families of graphs can be calculai ed by a transfer matrix method. The transfer matrix commutes with an action of the symmetric group on the colours. Using représentation theory, it is shown that the matrix is équivalent to a block-diagonal matrix. The multiplicities and the sizes of the blocks are obtained. Using a repeated inclusion-exclusion argument the ...
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ژورنال
عنوان ژورنال: Journal of Combinatorial Theory, Series B
سال: 1976
ISSN: 0095-8956
DOI: 10.1016/0095-8956(76)90062-9