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arXiv · 2404.05451

Estimates for the approximation characteristics of the Nikol'skii-Besov classes of functions with mixed smoothness in the space $B_{q,1}$

K. V. Pozharska·A. S. Romanyuk
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Abstract

Exact-order estimates are obtained for some approximation characteristics of the classes of periodic multivariate functions with mixed smoothness (the Nikol'skii-Besov classes $B^{\boldsymbol{r}}_{p, \theta}$) in the space $B_{q,1}$, $1 \leq p, q \leq \infty$, which norm is stronger than the $L_q$-norm. It is shown, that in the multivariate case (in contrast to the univariate) in most of the considered situations the obtained estimates differ in order from the corresponding estimates in the space $L_q$. Besides, a significant progress is made in estimates for the considered approximation characteristics of the classes $B^{\boldsymbol{r}}_{p, \theta}$ in the space $B_{q, 1}$ comparing to the known estimates in the space $L_q$.

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K. V. Pozharska, A. S. Romanyuk. 2024-04-08. Estimates for the approximation characteristics of the Nikol'skii-Besov classes of functions with mixed smoothness in the space $B_{q,1}$. https://arxiv.org/abs/2404.05451

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