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Best Approximations and Kolmogorov and Trigonometric Widths of the Classes B Ω p,θ of Periodic Functions of Many Variables

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Abstract

We obtain estimates exact in order for the best approximations and Kolmogorov and trigonometric widths of the classes B Ω p,θ of periodic functions of many variables in the space L q for certain values of the parameters p and q.

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  1. Institute of Mathematics, Ukrainian Academy of Sciences, Kiev, Ukraine

    S. A. Stasyuk

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Translated from Ukrains’kyi Matematychnyi Zhurnal, Vol. 56, No. 11, pp. 1557–1568, November, 2004.

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Stasyuk, S.A. Best Approximations and Kolmogorov and Trigonometric Widths of the Classes B Ω p,θ of Periodic Functions of Many Variables. Ukr Math J 56, 1849–1863 (2004). https://doi.org/10.1007/s11253-005-0155-1

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