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arXiv · 1508.06261

An extension of MacMahon's Equidistribution Theorem to ordered multiset partitions

Andrew Timothy Wilson
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Abstract

A classical result of MacMahon states that inversion number and major index have the same distribution over permutations of a given multiset. In this work we prove a strengthening of this theorem originally conjectured by Haglund. Our result can be seen as an equidistribution theorem over the ordered partitions of a multiset into sets, which we call ordered multiset partitions. Our proof is bijective and involves a new generalization of Carlitz's insertion method. This generalization leads to a new extension of Macdonald polynomials for hook shapes. We use our main theorem to show that these polynomials are symmetric and we give their Schur expansion.

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Andrew Timothy Wilson. 2015-08-25. An extension of MacMahon's Equidistribution Theorem to ordered multiset partitions. https://arxiv.org/abs/1508.06261

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