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Extreme Problems Related to the Approximation of the Lebesgue Constant of a Fourier Operator by a Logarithmic Function

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Abstract

The Lebesgue constant corresponding to the classical Fourier operator is approximated by a logarithmic function depending on two parameters. The difference between the Lebesgue constant and this function is studied, various extreme problems are considered, algorithms of successive reduction of values of the obtained best uniform approximations are given.

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Authors and Affiliations

  1. Naberezhnye Chelny State Pedagogical University, 423806, Naberezhnye Chelny, Russia

    I. A. Shakirov

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  1. I. A. Shakirov
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Correspondence to I. A. Shakirov.

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(Submitted by F. G. Avkhadiev)

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Shakirov, I.A. Extreme Problems Related to the Approximation of the Lebesgue Constant of a Fourier Operator by a Logarithmic Function. Lobachevskii J Math 41, 2287–2294 (2020). https://doi.org/10.1134/S1995080220110220

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  • DOI: https://doi.org/10.1134/S1995080220110220

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