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Interval pattern avoidance for arbitrary root systems

Alexander Woo
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Abstract

We extend the idea of interval pattern avoidance defined by Yong and the author for $S_n$ to arbitrary Weyl groups using the definition of pattern avoidance due to Billey and Braden, and Billey and Postnikov. We show that, as previously shown by Yong and the author for $GL_n$, interval pattern avoidance is a universal tool for characterizing which Schubert varieties have certain local properties, and where these local properties hold.

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Alexander Woo. 2006-11-11. Interval pattern avoidance for arbitrary root systems. https://arxiv.org/abs/math/0611328

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