We obtain the exact-order estimations for the approximation of the isotropic Nikol’skii–Besov classes of functions of several variables by the de la Vallée-Poussin-type sums in metrics of the spaces L ∞(ℝd) and L ∞(ℝd).
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Translated from Ukrains’kyi Matematychnyi Zhurnal, Vol. 67, No. 10, pp. 1423–1433, October, 2015.
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Yanchenko, S.Y. Approximation of Functions from the Isotropic Nikol’skii–Besov Classes in the Uniform and Integral Metrics. Ukr Math J 67, 1599–1610 (2016). https://doi.org/10.1007/s11253-016-1175-8
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DOI: https://doi.org/10.1007/s11253-016-1175-8