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arXiv · 1112.6014

Inversion polynomials for 321-avoiding permutations

Szu-En Cheng·Sergi Elizalde·Anisse Kasraoui·Bruce Sagan
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Abstract

We prove a generalization of a conjecture of Dokos, Dwyer, Johnson, Sagan, and Selsor giving a recursion for the inversion polynomial of 321-avoiding permutations. We also answer a question they posed about finding a recursive formulas for the major index polynomial of 321-avoiding permutations. Other properties of these polynomials are investigated as well. Our tools include Dyck and 2-Motzkin paths, polyominoes, and continued fractions.

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BibTeXRIS

Szu-En Cheng, Sergi Elizalde, Anisse Kasraoui, Bruce Sagan. 2012-11-20. Inversion polynomials for 321-avoiding permutations. https://arxiv.org/abs/1112.6014

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