Double absolute summability factor theorems and applications

Abstract

In an earlier paper the first author [Ekrem Savas, Factors for | A | k summability of infinite series, Comput. Math. Appl. 53 (7) (2007) 1045–1049. [3]] obtained a summability factor theorem for absolute summability of the order k ≥ 1 . In this paper we extend that result to doubly infinite matrices.