Approximation of the Lebesgue constant of the Fourier operator by a logarithmic-fractional-rational function
https://doi.org/10.26907/0021-3446-2023-11-75-85
Abstract
The Lebesgue constant of the classical Fourier operator is uniformly approximated by a logarithmic-fractional-rational function depending on three parameters; they are defined using the specific properties of logarithmic and rational approximations. A rigorous study of the corresponding residual term having an indefinite (non-monotonic) behavior has been carried out. The obtained approximation results strengthen the known results by more than two orders of magnitude.
About the Author
I. A. Shakirov
Naberezhnye Chelny State Pedagogical University
Russian Federation
Russian Federation
Iskander Asgatovich Shakirov
28 Nizametdinov str., Naberezhniye Chelny, 423806
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Review
For citations:
Shakirov I.A. Approximation of the Lebesgue constant of the Fourier operator by a logarithmic-fractional-rational function. Izvestiya Vysshikh Uchebnykh Zavedenii. Matematika. 2023;(11):75-85. (In Russ.) https://doi.org/10.26907/0021-3446-2023-11-75-85
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