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arXiv · 1705.08113

Noncommutative Bell polynomials and the dual immaculate basis

Jean-Christophe Novelli·Jean-Yves Thibon·Frédéric Toumazet
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Abstract

We define a new family of noncommutative Bell polynomials in the algebra of free quasi-symmetric functions and relate it to the dual immaculate basis of quasi-symmetric functions. We obtain noncommutative versions of Grinberg's results [Canad. J. Math. 69 (2017), 21--53], and interpret them in terms of the tridendriform structure of WQSym. We then present a variant of Rey's self-dual Hopf algebra of set partitions [FPSAC'07, Tianjin] adapted to our noncommutative Bell polynomials and give a complete description of the Bell equivalence classes as linear extensions of explicit posets.

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Jean-Christophe Novelli, Jean-Yves Thibon, Frédéric Toumazet. 2017-05-23. Noncommutative Bell polynomials and the dual immaculate basis. https://arxiv.org/abs/1705.08113

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