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arXiv · 2409.15659

A Bijection Between All Shi Regions and Core Partitions

Matthew Davis
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Abstract

We extend the bijection of Fishel-Vazirani on dominant regions of the $m$-Shi arrangement. Our map puts the set of all minimal chambers of the $m$-Shi arrangement of Type $A_{n}$ in bijection with a certain set of (equivalence classes of) $n$-core partitions. As a step to our proof, we give a potentially interesting classification of the alcoves in the $S_{n}$-orbit of an $m$-minimal alcove which are themselves $m$-minimal.

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Matthew Davis. 2024-09-24. A Bijection Between All Shi Regions and Core Partitions. https://arxiv.org/abs/2409.15659

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