Problems in the approximation of $2\pi $-periodic functions by Fourier sums in the space $L_2 (2\pi)$

DOI10.1023/B:MATN.0000049674.45111.71zbMath1114.42001OpenAlexW2058555917MaRDI QIDQ2387805

Publication date: 5 September 2005

Published in: Mathematical Notes (Search for Journal in Brave)

Full work available at URL: https://doi.org/10.1023/b:matn.0000049674.45111.71

zbMATH Keywords

Kolmogorov width Steklov function approximation by Fourier sums $2\pi $-periodic functions \varphi }^{r function classes $W_{2 k} $k} \) and \(W_{\varphi }^{r

Mathematics Subject Classification ID

Trigonometric approximation (42A10) Convergence and absolute convergence of Fourier and trigonometric series (42A20)

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Problems in the approximation of \(2\pi \)-periodic functions by Fourier sums in the space \(L_2 (2\pi)\)