Abstract
Sharp Jackson-Stechkin type inequalities in which the modulus of continuity of mth order of functions is defined via the Steklov function are obtained. For the classes of functions defined by these moduli of continuity, exact values of various n-widths are derived.
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Original Russian Text © M. Sh. Shabozov, K. Tukhliev, 2013, published in Matematicheskie Zametki, 2013, Vol. 94, No. 6, pp. 908–917.
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Shabozov, M.S., Tukhliev, K. Best polynomial approximations and the widths of function classes in L 2 . Math Notes 94, 930–937 (2013). https://doi.org/10.1134/S0001434613110291
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DOI: https://doi.org/10.1134/S0001434613110291