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arXiv · 2411.05334

The Double Almost-Riordan Arrays and Their Sequence Characterization, Compression, and Total Positivity

Tian-Xiao He
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Abstract

In this paper, we define double almost-Riordan arrays and find that the set of all double almost-Riordan arrays forms a group, called the double almost-Riordan group. We also obtain the sequence characteristics of double almost-Riordan arrays and give the production matrices for double almost-Riordan arrays. We define the compression of double almost-Riordan arrays and present their sequence characterization. Finally we give a characteristic for the total positivity of double Riordan arrays, by using which we discuss the total positivity for compressed double almost-Riordan arrays.

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Tian-Xiao He. 2024-11-08. The Double Almost-Riordan Arrays and Their Sequence Characterization, Compression, and Total Positivity. https://arxiv.org/abs/2411.05334

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