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arXiv · 1409.2595

Power sum expansion of chromatic quasisymmetric functions

Christos A. Athanasiadis
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Abstract

The chromatic quasisymmetric function of a graph was introduced by Shareshian and Wachs as a refinement of Stanley's chromatic symmetric function. An explicit combinatorial formula, conjectured by Shareshian and Wachs, expressing the chromatic quasisymmetric function of the incomparability graph of a natural unit interval order in terms of power sum symmetric functions, is proven. The proof uses a formula of Roichman for the irreducible characters of the symmetric group.

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Christos A. Athanasiadis. 2015-04-26. Power sum expansion of chromatic quasisymmetric functions. https://arxiv.org/abs/1409.2595

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