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arXiv · 2105.09774

Determinants of some pentadiagonal matrices

L. Losonczi
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Abstract

In this paper we consider pentadiagonal $(n+1)\times(n+1)$ matrices with two subdiagonals and two superdiagonals at distances $k$ and $2k$ from the main diagonal where $1\le k<2k\le n$. We give an explicit formula for their determinants and also consider the Toeplitz and "imperfect" Toeplitz versions of such matrices. Imperfectness means that the first and last $k$ elements of the main diagonal differ from the elements in the middle. Using the rearrangement due to Egerv\'ary and Sz\'asz we also show how these determinants can be factorized.

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L. Losonczi. 2021-05-18. Determinants of some pentadiagonal matrices. https://arxiv.org/abs/2105.09774

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