27 research outputs found
On Tauber's second Tauberian theorem
We study Tauberian conditions for the existence of Cesàro limits in terms of the Laplace transform. We also analyze Tauberian theorems for the existence of distributional point values in terms of analytic representations. The development of these theorems is parallel to Tauber's second theorem on the converse of Abel's theorem. For Schwartz distributions, we obtain extensions of many classical Tauberians for Cesàro and Abel summability of functions and measures. We give general Tauberian conditions in order to guarantee summability for a given order . The results are directly applicable to series and Stieltjes integrals, and we therefore recover the classical cases and provide new Tauberians for the converse of Abel's theorem where the conclusion is Cesàro summability rather than convergence. We also apply our results to give new quick proofs of some theorems of Hardy-Littlewood and Szàsz for Dirichlet series
A Tauberian theorem for Cesàro summability of integrals
AbstractIn this paper we give a proof of the generalized Littlewood Tauberian theorem for Cesàro summability of improper integrals
Comparison theorems for summability methods of sequences of fuzzy numbers
In this study we compare Ces\`{a}ro and Euler weighted mean methods of
summability of sequences of fuzzy numbers with Abel and Borel power series
methods of summability of sequences of fuzzy numbers. Also some results dealing
with series of fuzzy numbers are obtained.Comment: publication information is added, typos correcte
Indexed Absolute Summability Factor of Improper Integrals
In this paper, we have defined the summability for improper integrals and established a theorem on indexed absolute Cesaro summability factors of improper integral under sufficient conditions. Some auxiliary results (well known) have also been deduced from the main result under suitable conditions
Necessary and sufficient conditions under which convergence follows from summability by weighted means
We prove necessary and sufficient Tauberian conditions for sequences summable by weighted mean methods. The main results of this paper apply to all weighted mean methods and unify the results known in the literature for particular methods. Among others, the conditions in our theorems are easy consequences of the slowly decreasing condition for real numbers, or slowly
oscillating condition for complex numbers. Therefore, practically all classical (one-sided as well as two-sided) Tauberian conditions for weighted mean methods are corollaries of our two
main theorems
Wiener amalgams and summability of Fourier series
ome recent results on a general summability method, on the so-called
µ-summability is summarized. New spaces, such as Wiener amalgams, Feichtinger’s
algebra and modulation spaces are investigated in summability
theory. Sufficient and necessary conditions are given for the norm and a.e.
convergence of the µ-means.
Key Words: Wiener amalgam spaces, Feichtinger’s algebra, homogeneous
Banach spaces, Besov-, Sobolev-, fractional Sobolev spaces, modulation spaces,
Herz spaces, Hardy-Littlewood maximal function, µ-summability of Fourier
series, Lebesgue points.
AMS Classification Number: Primary 42B08, 46E30, Secondary 42B30,
42A3