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Differentiable functions and their Fourier coefficients

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Published/Copyright: January 6, 2022
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Abstract

In the paper we consider the properties of Fourier coefficients of functions that possess derivatives of bounded variation. We investigate the convergence of the special series of Fourier coefficients with respect to general orthonormal systems (ONS). The obtained results are the best possible. We also describe the behavior of subsequences of general ONS.

MSC 2010: 42C10

References

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Received: 2021-01-12
Revised: 2021-03-09
Accepted: 2021-03-30
Published Online: 2022-01-06
Published in Print: 2022-06-01

© 2022 Walter de Gruyter GmbH, Berlin/Boston

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