Extensions of the theorems of Szász and Zygmund on the absolute convergence of Fourier series

We consider the double Fourier series of functions / : T2 —> C, where T2 is the two-dimensional torus. We prove sufficient conditions on the convergence of the double series whose terms are the /3-th power of the absolute value of the Fourier coefficients of the function / in question. These cond...

Teljes leírás

Elmentve itt :
Bibliográfiai részletek
Szerző: Veres Antal
Dokumentumtípus: Cikk
Megjelent: Bolyai Institute, University of Szeged Szeged 2008
Sorozat:Acta scientiarum mathematicarum 74 No. 1-2
Kulcsszavak:Matematika, Fourier-sor
Tárgyszavak:
Online Access:http://acta.bibl.u-szeged.hu/16233
Leíró adatok
Tartalmi kivonat:We consider the double Fourier series of functions / : T2 —> C, where T2 is the two-dimensional torus. We prove sufficient conditions on the convergence of the double series whose terms are the /3-th power of the absolute value of the Fourier coefficients of the function / in question. These conditions are given in terms of moduli of continuity, of bounded variation in the sense of Vitali or Hardy and Krause, and of the mixed partial derivate in case / is an absolutely continuous function. Our results extend the classical theorems of O. Szász and A. Zygmund from single to double Fourier series.
Terjedelem/Fizikai jellemzők:191-206
ISSN:0001-6969