Repetition in reduced decompositions

Bridget Eileen Tenner

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arXiv · 1106.2839

Repetition in reduced decompositions

Bridget Eileen Tenner

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Abstract

Given a permutation w, we show that the number of repeated letters in a reduced decomposition of w is always less than or equal to the number of 321- and 3412-patterns appearing in w. Moreover, we prove bijectively that the two quantities are equal if and only if w avoids the ten patterns 4321, 34512, 45123, 35412, 43512, 45132, 45213, 53412, 45312, and 45231.

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BibTeX RIS

Bridget Eileen Tenner. 2012-01-05. Repetition in reduced decompositions. https://arxiv.org/abs/1106.2839

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