Abstract
In this paper, we investigate the strong summability of two-dimensional Walsh–Fourier series obtained in [F. Weisz, Strong convergence theorems for two-parameter Walsh–Fourier and trigonometric-Fourier series, Studia Math. 117 1996, 2, 173–194] (see Theorem W) and prove the sharpness of this result.
Funding source: Shota Rustaveli National Science Foundation
Award Identifier / Grant number: YS-18-043
Funding statement: The research was supported by Shota Rustaveli National Science Foundation grant YS-18-043.
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