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arXiv · 2212.13091

K-polynomials of multiplicity-free varieties

Federico Castillo·Yairon Cid-Ruiz·Fatemeh Mohammadi·Jonathan Montaño
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Abstract

We describe the twisted $K$-polynomial of multiplicity-free varieties in a multiprojective setting. More precisely, for multiplicity-free varieties, we show that the support of the twisted $K$-polynomial is a generalized polymatroid. As applications, we show that the support of the M\"obius function of a linear polymatroid is a generalized polymatroid, and we settle a conjecture of Monical, Tokcan and Yong regarding Grothendieck polynomials for the case of zero-one Schubert polynomials.

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Federico Castillo, Yairon Cid-Ruiz, Fatemeh Mohammadi, Jonathan Montaño. 2022-12-26. K-polynomials of multiplicity-free varieties. https://arxiv.org/abs/2212.13091

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