Generalizations of Kothe-Toeplitz duals and Null duals of new difference sequence spaces

摘要

The main purpose of the paper is to generalize the notions of the Kothe-Toeplitz duals and Null duals of sequence spaces by introducing the concepts of alpha EF-, beta EF-, gamma EF-duals and NEF-duals, where E = (E-n) and F = (F-n) are two partitions of finite subsets of the positive integers. These duals are computed for the classical sequence spaces l(infinity), c and c(0). The other purpose of the paper is to introduce the sequence spaces