Orlicz–Pettis Theorem through Summability Methods

Abstract

This paper unifies several versions of the Orlicz−Pettis theorem that incorporate summability methods. We show that a series is unconditionally convergent if and only if the series is weakly subseries convergent with respect to a regular linear summability method. This includes results using matrix summability, statistical convergence with respect to an ideal, and other variations of summability methods.

Keywords

• summability method
• ideal convergence
• weakly unconditional cauchy series
• orlicz–pettis theorem