We obtain exact-order estimates for the trigonometric widths of the classes \( B_{{p,\theta}}^{\varOmega } \) of periodic functions of many variables in the space L q for some relationships between the parameters p and q.
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Translated from Ukrains’kyi Matematychnyi Zhurnal, Vol. 64, No. 8, pp. 1041–1052, August, 2012.
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Derev’yanko, N.V. Trigonometric widths of classes of periodic functions of many variables. Ukr Math J 64, 1185–1198 (2013). https://doi.org/10.1007/s11253-013-0709-6
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DOI: https://doi.org/10.1007/s11253-013-0709-6