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arXiv · 2011.00849

Kippenhahn curves of some tridiagonal matrices

Natália Bebiano·Joáo da Providéncia·Ilya M. Spitkovsky·Kenya Vazquez
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Abstract

Tridiagonal matrices with constant main diagonal and reciprocal pairs of off-diagonal entries are considered. Conditions for such matrices with sizes up to 6-by-6 to have elliptical numerical ranges are obtained.

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Natália Bebiano, Joáo da Providéncia, Ilya M. Spitkovsky, Kenya Vazquez. 2020-11-02. Kippenhahn curves of some tridiagonal matrices. https://arxiv.org/abs/2011.00849

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