Abstract
For Sobolev classes of periodic functions of one variable with restrictions on higher derivatives in L 2, we determine the exact orders of relative widths characterizing the best approximation of a fixed set by its sections of given dimension in the spaces L q.
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Konovalov, V.N. Approximation of Sobolev Classes by Their Sections of Finite Dimension. Ukrainian Mathematical Journal 54, 795–805 (2002). https://doi.org/10.1023/A:1021635530578
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DOI: https://doi.org/10.1023/A:1021635530578