Summability of double Fourier series by Nörlund methods at a point

On Double Summability of Double Conjugate Fourier Series

H. K. Nigam and Kusum Sharma Department of Mathematics, Faculty of Engineering and Technology, Mody Institute of Technology and Science, Deemed University, Laxmangarh 332311, Sikar, Rajasthan, India Correspondence should be addressed to Kusum Sharma, [email protected] Received 20 January 2012; Accepted 1 March 2012 Academic Editor: Ram U. Verma Copyright q 2012 H. K. Nigam and K. Sha...

On the Restricted Cesaro Summability of Double Fourier Series

and po.biu, v), («, v), has been considered by a number of writers. Gergen and Littauer [4, Theorems IV and V] have treated the problem of the boundedness, and convergence in the Pringsheim sense, of ...

Logarithmic Summability of Fourier Series

A set of regular summations logarithmic methods is introduced. This set includes Riesz and Nörlund logarithmic methods as limit cases. The application to logarithmic summability of Fourier series of continuous and integrable functions are given. The kernels of these logarithmic methods for trigonometric system are estimated.

On absolute Nörlund summability factors

Determination of a jump by Fourier and Fourier-Chebyshev series

‎By observing the equivalence of assertions on determining the jump of a‎ ‎function by its differentiated or integrated Fourier series‎, ‎we generalize a‎ ‎previous result of Kvernadze‎, ‎Hagstrom and Shapiro to the whole class of‎ ‎functions of harmonic bounded variation‎. ‎This is achieved without the finiteness assumption on‎ ‎the number of discontinuities‎. ‎Two results on determination of ...