Journal of applied mathematics & informatics

The Korean Society for Computational and Applied Mathematics (한국전산응용수학회)
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APPROXIMATION OF LIPSCHITZ CLASS BY DEFERRED-GENERALIZED NÖRLUND (D𝛾𝛽.Npq) PRODUCT SUMMABILITY MEANS

  • JITENDRA KUMAR KUSHWAHA (Department of Mathematics and Statistics, Deen Dayal Upadhyaya Gorakhpur University) ;
  • LAXMI RATHOUR (Department of Mathematics, National Institute of Technology) ;
  • LAKSHMI NARAYAN MISHRA (Department of Mathematics, Vellore Institute of Technology) ;
  • KRISHNA KUMAR (Department of Mathematics and Statistics, Deen Dayal Upadhyaya Gorakhpur University)
  • Received : 2022.12.17
  • Accepted : 2023.06.22
  • Published : 2023.09.30
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Abstract

In this paper, we have determined the degree of approximation of function belonging of Lipschitz class by using Deferred-Generalized Nörlund (D𝛾𝛽.Npq) means of Fourier series and conjugate series of Fourier series, where {pn} and {qn} is a non-increasing sequence. So that results of DEGER and BAYINDIR [23] become special cases of our results.

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Acknowledgement

Krishna Kumar one of the authors, is grateful to CSIR, New Delhi, India for providing financial assistance in the form of Junior Research Fellowship (JRF) Ref.No.- 18/06/2017(i) EU-V, (CSIR-UGC NET JUNE-2017).

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