Abstract
The notion of a symmetric contour introduced by Stahl and further generalized by Gonchar and Rakhmanov in connection with theory of rational interpolants with free poles is recalled. Refinement of this notion proposed by Baratchart and the author is discussed.
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Notes
- 1.
A meromorphic function \( \Psi ({\boldsymbol{z}}) \) has a zero/pole divisor \( \sum _i m_i{\boldsymbol{x}}_i - \sum n_i{\boldsymbol{y}}_i \) if \( \Psi ({\boldsymbol{z}}) \) has a zero of order \( m_i \) at \( {\boldsymbol{x}}_i \), a pole of order \( n_i \) at \( {\boldsymbol{y}}_i \), and otherwise is non-vanishing and finite.
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Yattselev, M.L. (2021). S-Contours and Convergent Interpolation. In: Abakumov, E., Baranov, A., Borichev, A., Fedorovskiy, K., Ortega-Cerdà , J. (eds) Extended Abstracts Fall 2019. Trends in Mathematics(), vol 12. Birkhäuser, Cham. https://doi.org/10.1007/978-3-030-74417-5_27
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DOI: https://doi.org/10.1007/978-3-030-74417-5_27
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