Milnor Numbers of Projective Hypersurfaces and the Chromatic Polynomial of Graphs
نویسنده
چکیده
The chromatic polynomialχG(q) of a graph G counts the num-ber of proper colorings of G. We give an affirmative answer to the conjectureof Read and Rota-Heron-Welsh that the absolute values of the coefficients ofthe chromatic polynomial form a log-concave sequence. The proof is obtainedby identifyingχG(q) with a sequence of numerical invariants of a projectivehypersurface analogous to the Milnor number of a local analytic hypersurface.As a by-product of our approach, we obtain an analogue of Kouchnirenko’s
منابع مشابه
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