We obtain exact-order estimates for the best bilinear approximations of the classes \( S_{p,\theta }^\Omega B \) of periodic functions of many variables in the space L q under certain restrictions on the parameters p, q, and θ.
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Translated from Ukrains’kyi Matematychnyi Zhurnal, Vol. 63, No. 6, pp. 809–826, June, 2011.
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Solich, K.V. Best bilinear approximations of the classes \( S_{p,\theta }^\Omega B \) of periodic functions of many variables. Ukr Math J 63, 940–961 (2011). https://doi.org/10.1007/s11253-011-0554-4
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DOI: https://doi.org/10.1007/s11253-011-0554-4