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arXiv · 2209.13317

A two-parameter deformation of the quasi-shuffle and new bases of quasi-symmetric functions

Olivier Bouillot·Jean-Christophe Novelli·Jean-Yves Thibon
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Abstract

We define a two-parameter deformation of the quasi-shuffle by means of the formal group law associated with the exponential generating function of the homogeneous Eulerian polynomials, and construct bases of $QSym$ and $\WQSym$ whose product rule is given by this operation.

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Olivier Bouillot, Jean-Christophe Novelli, Jean-Yves Thibon. 2026-04-17. A two-parameter deformation of the quasi-shuffle and new bases of quasi-symmetric functions. https://arxiv.org/abs/2209.13317

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