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Approximation by de la Vallée-Poussin-type means of Fourier series in integral and Hölder metrics

  • Boris Golubov and Sergey Volosivets EMAIL logo
Published/Copyright: October 31, 2025
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Abstract

We estimate the degree of approximation by de la Vallée-Poussin-type means in L p , uniform and Hölder metric. Applications to conjugate functions are also given. Our results extend those of Leindler–Meir–Totik and Kim.

MSC 2020: 42A10; 42A24

Acknowledgements

The second author thanks an anonymous referee for his/her valuable suggestions.

References

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Received: 2025-05-05
Revised: 2025-07-29
Accepted: 2025-08-05
Published Online: 2025-10-31

© 2025 Walter de Gruyter GmbH, Berlin/Boston

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