One inequality about coefficients of the chromatic polynomials of graphs
Tan Hai-n · Journal of Northwest Normal University · 2013
This paper does some research in the chromatic polynomials of graphs and gives some recursive formulas for the sum for absolute-value coefficients of the chromatic polynomial on terms of certain graph operations.By these results,the sums for absolute-value coefficients of the chromatic polynomial for p-tree,multibridge graph and K4 homeomorph are obtained respectively.Furthermore,the lower and upper bounds on the sum for absolute-value coefficients of the chromatic polynomial are improved efficiently.Simultaneously,this article characters a necessary condition for Hamiltonian graph.