Adyghe Int. Sci. J. Vol. 24, No. 1. P. 23–35.
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DOI: https://doi.org/10.47928/1726-9946-2024-24-1-23-35
EDN: QFMIGO
MATHEMATICS
| MSC 34A08, 34B05 | Original Article |
Strong approximation of functions by double Fourier series in generalized Hölder spaces
Robert Andreevich Lasuriya
Doctor of Physical and Mathematical Sciences, Corresponding Member of the Academy of Sciences of Ukraine, Professor, Laureate of the State Prize named after G.A. Dzidzarya in the field of natural sciences, honored worker of the Higher School of the Republic of Abkhazia, ORCID: 0000-0003-2388-6070, rlasuria67@yandex.ru
Mariana Ramikovna Golava
Teacher, competitor of the Department of Mathematical Analysis, Physics and Mathematics Faculty, Abhaszsky state university, Sukhum, the Republic of Abkhazia, ORCID: 0000-0002-8704-6444, marianagolava@yandex.ru
Abstract. We study some problems of strong approximation of the functions of double Fourier series in the generalized Holder spases. Order-accurate estimates for the strong summability functionals of double Fourier series are established, as wel as their approximation properties in the indicated spases.
Keywords: Fourier series, strong approximation, Holder spaces, best approximation.
Funding. The work was not carried out within the framework of funds.
Competing interests. There are no conflicts of interest regarding authorship and publication.
Contribution and Responsibility. All authors contributed to this article. Authors are solely responsible for providing the final version of the article in print. The final version of the manuscript was approved by all authors.
For citation. Lasuria R. A., Golava M. R. Strong approximation of functions by double Fourier series in generalized Hölder spaces. Adyghe Int. Sci.~J. 2024. Vol. 24, No. 1. Pp. 23–35.
DOI: https://doi.org/10.47928/1726-9946-2024-24-1-23-35; EDN: QFMIGO.
Submitted 05.12.2023; approved after reviewing 21.02.2024; aeeepted for publication 01.03.2024.
© Lasuria R. A., Golava M. R., 2024
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