We consider the Fejér (or first arithmetic) means of double Fourier series of functions belonging to one of the Hardy spaces , , or . We prove that the maximal Fejér operator is bounded from or into weak-, and also bounded from into . These results extend those by Jessen, Marcinkiewicz, and Zygmund, which involve the function spaces , , and with 0 < μ < 1, respectively. We establish analogous results for the maximal conjugate Fejér operators. On closing, we formulate two conjectures.
@article{bwmeta1.element.bwnjournal-article-smv116i1p89bwm, author = {Ferenc M\'oricz}, title = {On the maximal Fej\'er operator for double Fourier series of functions in Hardy spaces}, journal = {Studia Mathematica}, volume = {113}, year = {1995}, pages = {89-100}, zbl = {0842.47020}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-smv116i1p89bwm} }
Móricz, Ferenc. On the maximal Fejér operator for double Fourier series of functions in Hardy spaces. Studia Mathematica, Tome 113 (1995) pp. 89-100. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-smv116i1p89bwm/
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