Abstract
We establish the best approximation estimates for certain convolutions whose kernels are entire functions of exponential type in terms of the second modulus of continuity. The Jackson-type inequalities for even-order derivatives are particular cases of our estimates.
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Original Russian Text Copyright © 2014 Vinogradov O.L.
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Translated from Sibirskiĭ Matematicheskiĭ Zhurnal, Vol. 55, No. 3, pp. 494–508, May–June, 2014.
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Vinogradov, O.L. Approximation estimates for convolution classes in terms of the second modulus of continuity. Sib Math J 55, 402–414 (2014). https://doi.org/10.1134/S0037446614030021
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DOI: https://doi.org/10.1134/S0037446614030021