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Catalan numbers and Schubert polynomials for $w=1(n+1)... 2$

Alexander Woo
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Abstract

We show that the Schubert polynomial S_w specializes to the Catalan number C_n when $w=1(n+1)...2$. Several proofs of this result as well as a q-analog are given. An application to the singularities of Schubert varieties is given.

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Alexander Woo. 2004-07-09. Catalan numbers and Schubert polynomials for $w=1(n+1)... 2$. https://arxiv.org/abs/math/0407160

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