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arXiv · 1508.07030

A generalized SXP rule proved by bijections and involutions

Mark Wildon
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Abstract

This paper proves a combinatorial rule expressing the product $s_τ(s_{λ/μ} \circ p_r)$ of a Schur function and the plethysm of a skew Schur function with a power sum symmetric function as an integral linear combination of Schur functions. This generalizes the SXP rule for the plethysm $s_λ\circ p_r$. Each step in the proof uses either an explicit bijection or a sign-reversing involution. The proof is inspired by an earlier proof of the SXP rule due to Remmel and Shimozono, A simple proof of the Littlewood--Richardson rule and applications, Discrete Mathematics 193 (1998) 257--266. The connections with two later combinatorial rules for special cases of this plethysm are discussed. Two open problems are raised. The paper is intended to be readable by non-experts.

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Mark Wildon. 2016-10-09. A generalized SXP rule proved by bijections and involutions. https://arxiv.org/abs/1508.07030

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