ArticleOriginal scientific text
Title
Strong convergence theorems for two-parameter Walsh-Fourier and trigonometric-Fourier series
Authors 1
Affiliations
- Department of Numerical Analysis, Eötvös L. University, Múzeum krt. 6-8, H-1088 Budapest, Hungary
Abstract
The martingale Hardy space and the classical Hardy space are introduced. We prove that certain means of the partial sums of the two-parameter Walsh-Fourier and trigonometric-Fourier series are uniformly bounded operators from to (0 < p ≤ 1). As a consequence we obtain strong convergence theorems for the partial sums. The classical Hardy-Littlewood inequality is extended to two-parameter Walsh-Fourier and trigonometric-Fourier coefficients. The dual inequalities are also verified and a Marcinkiewicz-Zygmund type inequality is obtained for BMO spaces.
Keywords
martingale and classical Hardy spaces, p-atom, atomic decomposition, Walsh functions, Hardy-Littlewood inequality
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