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An efficient method for construction of J-unitary matrix polynomials is proposed, associated with companion matrix functions the last row of which is a polynomial in 1/t. The method relies on Wiener-Hopf factorization theory and stems from recently developed J-spectral factorization algorithm for certain Hermitian matrix functions.

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The first and the third authors were partially supported by Faculty Research funding from the Division of Science and Mathematics, NYUAD and H2020-MSCA-RISE-2020 grant ID: 101008140.

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Correspondence to Ilya M. Spitkovsky.

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Ephremidze, L., Saatashvili, A. & Spitkovsky, I.M. ON J-UNITARY MATRIX POLYNOMIALS. J Math Sci 266, 196–209 (2022).

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