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arXiv · 1109.4522

An algorithm for semistandardising homomorphisms

Matthew Fayers
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Abstract

Suppose $μ$ is a partition of $n$ and $λ$ a composition of $n$, and let $S^μ$, $M^λ$ denote the Specht module and permutation module defined by Dipper and James for the Iwahori--Hecke algebra $\mathscr{H}_n$ of the symmetric group $\mathfrak{S}_n$. We give an explicit fast algorithm for expressing a tableau homomorphism $\hatϕ_A:S^μ\to M^λ$ as a linear combination of semistandard homomorphisms. Along the way we provide a utility result related to removing rows from tableaux.

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BibTeXRIS

Matthew Fayers. 2012-05-15. An algorithm for semistandardising homomorphisms. https://doi.org/10.1016/j.jalgebra.2012.04.020

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