Uniform approximations by Fourier sums on classes of convolutions with generalized Poisson kernels

Authors

  • А.S. Serdyuk Institute of Matematics of the NAS of Ukraine, Kiev
  • Т.А. Stepanyuk Institute of Matematics of the NAS of Ukraine, Kiev

DOI:

https://doi.org/10.15407/dopovidi2016.11.010

Keywords:

asymptotic equality, Fourier sums, generalized Poisson kernels, Kolmogorov—Nikol'skii problem

Abstract

We find asymptotic unimprovable equalities for exact upper bounds of approximations by Fourier sums in a uniform metric on the classes of 2π-periodic functions representable in the form of convolutions of functions φ, which belong to unit balls of spaces Lp, with generalized Poisson kernels. For the obtained asymptotic equalities, we introduce the estimate of a remainder, which is expressed in the explicit form via absolute constants and parameters of the problem. This can be useful for practical application.

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References

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Published

23.12.2024

How to Cite

Serdyuk А., & Stepanyuk Т. (2024). Uniform approximations by Fourier sums on classes of convolutions with generalized Poisson kernels . Reports of the National Academy of Sciences of Ukraine, (11), 10–16. https://doi.org/10.15407/dopovidi2016.11.010