THE NOVEL TAUBERIAN CONDITIONS ASSOCIATED WITH THE (N-p-q) SUMMABILITY OF DOUBLE SEQUENCES

Abstract

. In this paper our primary objective is to provide a fresh perspective on the relationship between the (N (p q)) method which is a product of relevant one-dimensional summability methods and P-convergence for double sequences. To accomplish this objective we establish certain Tauberian conditions that control the behavior of a double sequence in terms of both O-L-oscillation and 0oscillation in certain senses building a bridge between (N (p q)) summability and P-convergence while imposing certain restrictions on the weight sequences. As special circumstances of our findings we demonstrate that Landau-type O-L condition with respect to (Pm) and (CM as well as Hardy-type 0 condition with respect to (P-m) and (Q(n)) serve as Tauberian conditions for (N (p q)) summability under particular additional conditions. Consequently these results encompass all classical Tauberian theorems including conditions such as slow decrease or slow oscillation in certain senses.