English

Estimates of best $m$-term trigonometric approximation of classes of analytic functions

Classical Analysis and ODEs 2016-03-08 v1

Abstract

In metric of spaces Ls, 1sL_{s}, \ 1\leq s\leq\infty, we obtain exact in order estimates of best mm-term trigonometric approximations of classes of convolutions of periodic functions, that belong to unit all of space Lp, 1pL_{p}, \ 1\leq p\leq\infty, with generated kernel Ψβ(t)=k=1ψ(k)cos(ktβπ2)\Psi_{\beta}(t)=\sum\limits_{k=1}^{\infty}\psi(k)\cos(kt-\frac{\beta\pi}{2}), βR\beta\in \mathbb{R}, whose coefficients ψ(k)\psi(k) tend to zero not slower than geometric progression. Obtained estimates coincide in order with approximation by Fourier sums of the given classes of functions in LsL_{s}-metric. This fact allows to write down exact order estimates of best orthogonal trigonometric approximation and trigonometric widths of given classes.

Keywords

Cite

@article{arxiv.1410.3866,
  title  = {Estimates of best $m$-term trigonometric approximation of classes of analytic functions},
  author = {A. S. Serdyuk and T. A. Stepaniuk},
  journal= {arXiv preprint arXiv:1410.3866},
  year   = {2016}
}

Comments

7 pages, in Ukrainian