On summability of double sequences (I)

Cesàro Summability of Double Sequences of Sets

In this paper, we study the concepts of Wijsman Cesàro summability and Wijsman lacunary convergence of double sequences of sets and investigate the relationship between them.

$mathcal{I}_2$-convergence of double sequences of\ fuzzy numbers

In this paper, we introduce and study the concepts of $mathcal{I}_2$-convergence, $mathcal{I}_2^{*}$-convergence for double sequences of fuzzy real numbers, where $mathcal{I}_2$ denotes the ideal of subsets of $mathbb N times mathbb N$. Also, we study some properties and relations of them.

On Summability of Double Series*

Some Summability Spaces of Double Sequences of Fuzzy Numbers

In this article we introduce and study the notions of double -lacunary strongly summable, double  Cesàro strongly summable, double  statistically convergent and double  -lacunary statistically convergent sequence of fuzzy numbers. Consequently we construct the spaces   2 F L  ,   2 F   ,   2 F S  and   2 F S  respectively and investigate the relationship among these spaces. F...

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...