On approximation in generalized Zygmund class

• Autorzy: Nigam Hare Krishna

Identyfikatory

DOI

10.1515/dema-2019-0022

• Języki publikacji: EN

Abstrakty

EN

Here, we estimate the degree of approximation of a conjugate function ğ and a derived conjugate function ğ′, of a 2 π-periodic function g ∈ Zλr, r ≥ 1, using Hausdorff means of CFS (conjugate Fourier series) and CDFS (conjugate derived Fourier series) respectively. Our main theorems generalize four previously known results. Some important corollaries are also deduced from our main theorems. We also partially review the earlier work of the authors in respect of order of the Euler-Hausdorff product method.

Słowa kluczowe

EN

generalized Zygmund (Zλr, r ≥ 1) class of function; error approximation; CFS; conjugate Fourier series; CDFS; conjugate derived Fourier series; generalized Minkowski’s inequality; Hausdorff means

PL

aproksymacja; błąd aproksymacji; przybliżenie; szeregi Fouriera; sprzężone szeregi Fouriera; nierówność Minkowskiego

• Wydawca: De Gruyter
• Czasopismo: Demonstratio Mathematica
• Rocznik: 2019
• Tom: Vol. 52, nr 1
• Strony: 370--387
• Opis fizyczny: Bibliogr. 43 poz.

Twórcy

autor

Nigam Hare Krishna

• Department of Mathematics, Central University of South Bihar, Gaya, Bihar, India

Bibliografia

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Uwagi

PL

Opracowanie rekordu w ramach umowy 509/P-DUN/2018 ze środków MNiSW przeznaczonych na działalność upowszechniającą naukę (2019).