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Lascoux Polynomials and Subdivisions of Gelfand–Zetlin Polytopes
International Mathematics Research Notices. 2024. Vol. 2024. No. 19. P. 12954–12977.
We give a new combinatorial description for Grassmannian Grothendieck polynomials in terms of subdivisions of Gelfand–Zetlin polytopes. Moreover, these subdivisions also provide a description of Lascoux polynomials. This generalizes a similar result on key polynomials by Kiritchenko, Smirnov, and Timorin.
Keywords: многогранник Гельфанда-ЦетлинаGelfand-Zetlin polytopeDemazure modulesLascoux polynomialмногочлен Ласкумодуль Демазюра
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