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arXiv · 2410.13129

Structural properties of a symmetric Toeplitz and Hankel matrices

Hojin Chu·Homoon Ryu
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Abstract

In this paper, we investigate properties of a symmetric Toeplitz matrix and a Hankel matrix by studying the components of its graph. To this end, we introduce the notion of ``weighted Toeplitz graph" and ``weighted Hankel graph", which are weighted graphs whose adjacency matrix are a symmetric Toeplitz matrix and a Hankel matrix, respectively. By studying the components of a weighted Toeplitz graph, we show that the Frobenius normal form of a symmetric Toeplitz matrix is a direct sum of symmetric irreducible Toeplitz matrices. Similarly, by studying the components of a weighted Hankel matrix, we show that the Frobenius normal form of a Hankel matrix is a direct sum of irreducible Hankel matrices.

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Hojin Chu, Homoon Ryu. 2024-10-17. Structural properties of a symmetric Toeplitz and Hankel matrices. https://doi.org/10.1016/j.laa.2024.11.025

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