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arXiv · 2411.14693

Minimum transformation representations of diagram monoids

Reinis Cirpons·James East·James D. Mitchell
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Abstract

We obtain formulae for the minimum transformation degrees of the most well-studied families of finite diagram monoids, including the partition, Brauer, Temperley--Lieb and Motzkin monoids. For example, the partition monoid $P_n$ has degree $1 + \frac{B(n+2)-B(n+1)+B(n)}2$ for $n\geq2$, where these are Bell numbers. The proofs involve constructing explicit faithful representations of the minimum degree, many of which can be realised as (partial) actions on projections.

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Reinis Cirpons, James East, James D. Mitchell. 2024-11-22. Minimum transformation representations of diagram monoids. https://arxiv.org/abs/2411.14693

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