We say that two permutations $\pi $ and $\rho $ have separated descents at position $k$ if $\pi $ has no descents before position $k$ and $\rho $ has no descents after position $k$. We give a counting formula, in terms of reduced word tableaux, for computing the structure constants of products of Schubert polynomials indexed by permutations with separated descents, and recognize that these structure constants are certain Edelman–Greene coefficients. Our approach uses generalizations of Schützenberger’s jeu de taquin algorithm and the Edelman–Greene correspondence via bumpless pipe dreams.
more » « less NSFPAR ID:
 10379302
 Publisher / Repository:
 Oxford University Press
 Date Published:
 Journal Name:
 International Mathematics Research Notices
 Volume:
 2023
 Issue:
 20
 ISSN:
 10737928
 Format(s):
 Medium: X Size: p. 1746117493
 Size(s):
 ["p. 1746117493"]
 Sponsoring Org:
 National Science Foundation
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