Abstract
We investigate the problem of the approximation of the classes \(C^{{\bar \psi }} H_{\omega }\) introduced by Stepanets in 1996 by the de la Valée-Poussin sums. We obtain asymptotic equalities that give a solution of the Kolmogorov–Nikol'skii problem for the de la Valée-Poussin sums on the classes \(C^{{\bar \psi }} H_{\omega }\) in several important cases.
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Rukasov, V.I., Chaichenko, S.O. Approximation of the Classes \(C^{{\bar \psi }} H_{\omega }\) by de la Vallée-Poussin Sums. Ukrainian Mathematical Journal 54, 839–851 (2002). https://doi.org/10.1023/A:1021643732395
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DOI: https://doi.org/10.1023/A:1021643732395