ALGEBRAIC COMBINATORICS

no. 2

Derivatives of Schubert polynomials and proof of a determinant conjecture of Stanley
Algebraic Combinatorics, Volume 3 (2020) no. 2, pp. 301-307.

We study the action of a differential operator on Schubert polynomials. Using this action, we first give a short new proof of an identity of I. Macdonald (1991). We then prove a determinant conjecture of R. Stanley (2017). This conjecture implies the (strong) Sperner property for the weak order on the symmetric group, a property recently established by C. Gaetz and Y. Gao (2019).

Received: 2019-01-03
Revised: 2019-08-05
Accepted: 2019-08-08
Published online: 2020-04-01
DOI: https://doi.org/10.5802/alco.93
Classification: 05E05,  06A07,  15A15,  05E10
Keywords: Sperner property, weak order, Schubert polynomial, Macdonald identity 
@article{ALCO_2020__3_2_301_0,
     author = {Hamaker, Zachary and Pechenik, Oliver and Speyer, David E and Weigandt, Anna},
     title = {Derivatives of Schubert polynomials and proof of a determinant conjecture of Stanley},
     journal = {Algebraic Combinatorics},
     pages = {301--307},
     publisher = {MathOA foundation},
     volume = {3},
     number = {2},
     year = {2020},
     doi = {10.5802/alco.93},
     language = {en},
     url = {alco.centre-mersenne.org/item/ALCO_2020__3_2_301_0/}
}
Hamaker, Zachary; Pechenik, Oliver; Speyer, David E; Weigandt, Anna. Derivatives of Schubert polynomials and proof of a determinant conjecture of Stanley. Algebraic Combinatorics, Volume 3 (2020) no. 2, pp. 301-307. doi : 10.5802/alco.93. https://alco.centre-mersenne.org/item/ALCO_2020__3_2_301_0/

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