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A categorification for the chromatic polynomial

Laure Helme-Guizon·Yongwu Rong
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Abstract

For each graph we construct graded cohomology groups whose graded Euler characteristic is the chromatic polynomial of the graph. We show the cohomology groups satisfy a long exact sequence which corresponds to the well-known deletion-contraction rule. This work is motivated by Khovanov's work on categorification of the Jones polynomial of knots.

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Laure Helme-Guizon, Yongwu Rong. 2005-10-18. A categorification for the chromatic polynomial. https://doi.org/10.2140/agt.2005.5.1365

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