Abstract
We present the results concerning the approximation of \(\bar \psi \)-differentiable functions of many variables by rectangular Fourier sums in uniform and integral metrics and establish estimates for the ϕ-strong means of their deviations in terms of the best approximations.
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Translated from Ukrains’kyi Matematychnyi Zhurnal, Vol. 59, No. 8, pp. 1075–1093, August, 2007.
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Stepanets, A.I., Lasuriya, R.A. Multiple Fourier sums and ϕ-strong means of their deviations on the classes of \(\bar \psi \)-differentiable functions of many variables. Ukr Math J 59, 1192–1211 (2007). https://doi.org/10.1007/s11253-007-0080-6
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DOI: https://doi.org/10.1007/s11253-007-0080-6