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Interval Pattern Avoidance for Arbitrary Root Systems

Published online by Cambridge University Press:  20 November 2018

Alexander Woo
Alexander Woo*
Affiliation:
Department of Mathematics, Statistics and Computer Science, St. Olaf College, Northfield, MN, U.S.A. e-mail: woo@stolaf.edu
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Abstract

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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 $\text{G}{{\text{L}}_{n}}$, interval pattern avoidance is a universal tool for characterizing which Schubert varieties have certain local properties, and where these local properties hold.

Keywords

14M1505E15
Type
Research Article
Information
Canadian Mathematical Bulletin , Volume 53 , Issue 4 , 01 December 2010 , pp. 757 - 762
Copyright
Copyright © Canadian Mathematical Society 2010

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