Abstract
We establish estimates for classic approximation quantities for sets from functional spaces (classes of functions analytic in Jordan domains), namely, for the best polynomial approximations and Kolmogorov widths.
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Institute of Mathematics, Ukrainian Academy of Sciences, Kiev. Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 51, No. 5, pp. 645–662, May, 1999.
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Romanyuk, V.S. Weighted approximation in mean of classes of analytic functions by algebraic polynomials and finite-dimensional subspaces. Ukr Math J 51, 716–734 (1999). https://doi.org/10.1007/BF02591707
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DOI: https://doi.org/10.1007/BF02591707