In this paper, we define and study a general class of convolution operators based on Landau operators. A property of these new operators is that they reproduce the affine functions, a feature less commonly encountered by integral type operators. Approximation properties in different function spaces are obtained, including quantitative Voronovskaya-type results.


Octavian Agratini
Babeş-Bolyai University, Cluj-Napoca, Romania
Tiberiu Popoviciu Institute of Numerical Analysis, Romanian Academy

Sorin G. Gal
University of Oradea, Romania
Academy of Romanian Scientists


Landau operator; modulus of continuity; weighted space; approximation process; upper estimates; quantitative Voronovskaya-type theorems


Cite this paper as:

O. Agratini, S.G. Gal,  On Landau-type approximation operators, Mediterranean Journal of Mathematics, 18 (2021) art. no. 64, https://doi.org/10.1007/s00009-021-01712-w

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