Abstract
We obtain order-sharp estimates of the orthogonal projection widths of the classes B Ω p,θ of periodic functions of several variables whose majorant of the mixed moduli of continuity contains both exponential and logarithmic multipliers.
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Original Russian Text © A. F. Konograi, 2014, published in Matematicheskie Zametki, 2014, Vol. 95, No. 5, pp. 734–749.
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Konograi, A.F. Estimates of the approximation characteristics of the classes B Ω p,θ of periodic functions of several variables with given majorant of mixed moduli of continuity. Math Notes 95, 656–669 (2014). https://doi.org/10.1134/S0001434614050095
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DOI: https://doi.org/10.1134/S0001434614050095