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Absolute convergence factors of Lipschitz class functions for general Fourier series

  • Vakhtang Tsagareishvili EMAIL logo und Giorgi Tutberidze
Veröffentlicht/Copyright: 10. Oktober 2021
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Abstract

The main aim of this paper is to investigate the sequences of positive numbers, for which multiplication with Fourier coefficients of functions f Lip 1 class provides absolute convergence of Fourier series. In particular, we found special conditions for the functions of orthonormal system (ONS), for which the above sequences are absolute convergence factors of Fourier series of functions of Lip 1 class. It is established that the resulting conditions are best possible in certain sense.

MSC 2010: 42C10; 46B07

Funding statement: The research was supported by Shota Rustaveli National Science Foundation grant PHDF-18-476.

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Received: 2020-01-15
Revised: 2020-04-09
Accepted: 2020-06-23
Published Online: 2021-10-10
Published in Print: 2022-04-01

© 2021 Walter de Gruyter GmbH, Berlin/Boston

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