Absolute Riesz Summability of Fourier Series. I

Local property of absolute weighted mean summability of Fourier series

We improve and generalize a result on a local property of |T |k summability of factored Fourier series due to Sarıgöl [6].

On absolute generalized Norlund summability of double orthogonal series

In the paper [Y. Okuyama, {it On the absolute generalized N"{o}rlund summability of orthogonal series},Tamkang J. Math. Vol. 33, No. 2, (2002), 161-165] the author has found some sufficient conditions under which an orthogonal seriesis summable $|N,p,q|$ almost everywhere. These conditions are expressed in terms of coefficients of the series. It is the purpose ofthis paper to extend this result...

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 l-1 Riesz Summability of the Inverse Fourier Integral

A New Factor Theorem on Absolute Riesz Summability