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arXiv · 2303.07658

Sign-twisted generating functions of the odd length for Weyl groups of type $D$

Haihang Gu·Houyi Yu
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Abstract

The odd length in Weyl groups is a new statistic analogous to the classical Coxeter length, and features combinatorial and parity conditions. We establish explicit closed product formulas for the sign-twisted generating functions of the odd length for parabolic quotients of Weyl groups of type $D$. As a consequence, we verify three conjectures of Brenti and Carnevale on evaluating closed forms for these generating functions. We then give an equivalent condition for the sign-twisted generating functions to be expressible as products of cyclotomic polynomials, settling a conjecture of Stembridge.

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Haihang Gu, Houyi Yu. 2023-03-14. Sign-twisted generating functions of the odd length for Weyl groups of type $D$. https://arxiv.org/abs/2303.07658

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