A sharp estimate of the measure of the set of divergence of multiple orthogonal Fourier series
Tom 159 / 2003
Studia Mathematica 159 (2003), 33-50 MSC: Primary 42B08; Secondary 40B05. DOI: 10.4064/sm159-1-2
The aim of this paper is to obtain sharp estimates from below of the measure of the set of divergence of the $m$-fold Fourier series with respect to uniformly bounded orthonormal systems for the so-called $G$-convergence and $\lambda $-restricted convergence. We continue the study begun in a previous work.