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arXiv · 1609.07335

On rotated Schur-positive sets

Sergi Elizalde·Yuval Roichman
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Abstract

The problem of finding Schur-positive sets of permutations, originally posed by Gessel and Reutenauer, has seen some recent developments. Schur-positive sets of pattern-avoiding permutations have been found by Sagan et al and a general construction based on geometric operations on grid classes has been given by the authors. In this paper we prove that horizontal rotations of Schur-positive subsets of permutations are always Schur-positive. The proof applies a cyclic action on standard Young tableaux of certain skew shapes and a jeu-de-taquin type straightening algorithm. As a consequence of the proof we obtain a notion of cyclic descent set on these tableaux, which is rotated by the cyclic action on them.

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Sergi Elizalde, Yuval Roichman. 2016-09-23. On rotated Schur-positive sets. https://arxiv.org/abs/1609.07335

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