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arXiv · 1506.01116

A remark on the trigonometric system

Alexander Kushpel
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Abstract

We present a new property of the trigonometric system arranged in a natural order. It is shown that the sequence of subspaces of trigonometric polynomials is optimal in the sense of order of convergence on convolution classes K*Up in Lq for any 1<p,q<\infty just in the cases of "very slow" or "very fast" rate of decay of Fourier coefficients of K.

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Alexander Kushpel. 2015-06-03. A remark on the trigonometric system. https://arxiv.org/abs/1506.01116

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