## Annals of Functional Analysis

### On an approximation of $2$-dimensional Walsh–Fourier series in martingale Hardy spaces

#### Abstract

In this paper, we investigate convergence and divergence of partial sums with respect to the $2$-dimensional Walsh system on the martingale Hardy spaces. In particular, we find some conditions for the modulus of continuity which provide convergence of partial sums of Walsh–Fourier series. We also show that these conditions are in a sense necessary and sufficient.

#### Article information

Source
Ann. Funct. Anal. Volume 9, Number 1 (2018), 137-150.

Dates
Received: 29 November 2016
Accepted: 11 March 2017
First available in Project Euclid: 5 October 2017

Permanent link to this document
https://projecteuclid.org/euclid.afa/1507169076

Digital Object Identifier
doi:10.1215/20088752-2017-0032

#### Citation

Persson, L. E.; Tephnadze, G.; Wall, P. On an approximation of $2$ -dimensional Walsh–Fourier series in martingale Hardy spaces. Ann. Funct. Anal. 9 (2018), no. 1, 137--150. doi:10.1215/20088752-2017-0032. https://projecteuclid.org/euclid.afa/1507169076

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