Connection between Schubert polynomials and top Lascoux polynomials
Algebraic Combinatorics, Volume 8 (2025) no. 4, pp. 955-970.

Schubert polynomials form a basis of the polynomial ring $\mathbb{Q}[x_1, x_2, \dots ]$. This basis and its structure constants have received extensive study. Recently, Pan and Yu initiated the study of top Lascoux polynomials. These polynomials form a basis of the vector space $\widehat{V}$, a sub-algebra of $\mathbb{Q}[x_1, x_2, \dots ]$ where each graded piece has finite dimension. This paper connects Schubert polynomials and top Lascoux polynomials via a simple operator. We use this connection to show these two bases share the same structure constants. We also translate several results on Schubert polynomials to top Lascoux polynomials, including combinatorial formulas for their monomial expansions and supports.

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DOI: 10.5802/alco.439
Classification: 05E05
Keywords: Schubert polynomials, Lascoux polynomials, Key polynomials

Yu, Tianyi 1

1 Laboratoire d’Algèbre, de Combinatoire et d’Informatique Mathématique (LACIM) 201 avenue du Président Kennedy Montréal, Québec, H2X 3Y7, Canada
License: CC-BY 4.0
Copyrights: The authors retain unrestricted copyrights and publishing rights
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Yu, Tianyi. Connection between Schubert polynomials and top Lascoux polynomials. Algebraic Combinatorics, Volume 8 (2025) no. 4, pp. 955-970. doi : 10.5802/alco.439. https://alco.centre-mersenne.org/articles/10.5802/alco.439/

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