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Akishev G. On estimates of the order of the best M–term approximations of functions of several variables in the anisotropic Lorentz – Zygmund space. Izvestiya of Saratov University. Mathematics. Mechanics. Informatics, 2023, vol. 23, iss. 2, pp. 142-156. DOI: 10.18500/1816-9791-2023-23-2-142-156, EDN: YKNUUN

This is an open access article distributed under the terms of Creative Commons Attribution 4.0 International License (CC-BY 4.0).
Published online: 
31.05.2023
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Language: 
Russian
Heading: 
Mathematics
Article type: 
Article
UDC: 
517.51
DOI: 
10.18500/1816-9791-2023-23-2-142-156
EDN: 
YKNUUN

On estimates of the order of the best M–term approximations of functions of several variables in the anisotropic Lorentz – Zygmund space

Autors: 
Akishev Gabdolla, Kazakhstan Branch of Lomonosov Moscow State University
Abstract: 

The article considers the anisotropic  Lorentz – Karamata space of periodic functions of several variables and the Nikol'skii – Besov class in this space. The order-sharp estimates are established for the best $M$-term trigonometric approximations of functions from the Nikol'skii-Besov class in the norm of another Lorentz – Zygmund space.

Key words: 
Lorentz – Zygmund space
Nikol'skii – Besov class
M-term approximation
Acknowledgments: 
This work was supported by the Ministry of Education and Science of the Republic of Kazakhstan (project AP 08855579).
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Received: 
24.02.2022
Accepted: 
01.11.2022
Published: 
31.05.2023
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