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arXiv · 2412.05461

The Triple Riordan Group

Paul Barry
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Abstract

We define the triple Riordan group, whose elements consist of $4$-tuples of power series $(g, f_1, f_2, f_3)$ with $g\in \mathbf{R}[[x^3]]$, and $f_1, f_2, f_3 \in x\mathbf{R}[[x^3]]$, for an appropriate ring $\mathbf{R}$. The construction of this group generalizes that of the double Riordan group, and lays the pattern for further generalizations.

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Paul Barry. 2024-12-06. The Triple Riordan Group. https://arxiv.org/abs/2412.05461

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