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arXiv · 2410.16758

Polynomial Expressions for the Dimensions of the Representations of Symmetric Groups and Restricted Standard Young Tableaux

Avichai Cohen·Shaul Zemel
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Abstract

Given a partition $\lambda$ of a number $k$, it is known that by adding a long line of length $n-k$, the dimension of the associated representation of $S_{n}$ is an integer-valued polynomial of degree $k$ in $n$. We show that its expansion in the binomial basis is bounded by the length of $\lambda$, and that the resulting coefficient of index $h$, with alternating signs, counts the standard Young tableaux of shape $\lambda$ in which a given collection of consecutive $h$ numbers lie in increasing rows. We also construct bijections in order to demonstare explicitly that this number is indeed independent of the set of consecutive $h$ numbers used.

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Avichai Cohen, Shaul Zemel. 2024-10-22. Polynomial Expressions for the Dimensions of the Representations of Symmetric Groups and Restricted Standard Young Tableaux. https://arxiv.org/abs/2410.16758

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