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arXiv · 2009.02138

Counting Signed Vexillary Permutations

Yibo Gao·Kaarel Hänni
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Abstract

We show that the number of signed permutations avoiding 1234 equals the number of signed permutations avoiding 2143 (also called vexillary signed permutations), resolving a conjecture by Anderson and Fulton. The main tool that we use is the generating tree developed by West. Many further directions are mentioned in the end.

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Yibo Gao, Kaarel Hänni. 2020-09-04. Counting Signed Vexillary Permutations. https://arxiv.org/abs/2009.02138

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