International Journal of Mathematics and Mathematical Sciences
Volume 23 (2000), Issue 2, Pages 119-122
doi:10.1155/S0161171200001861

Noninclusion theorems: Some remarks on a paper by J. A. Fridy

W. Beekmann

Fachbereich Mathematik, Fern Universität-Gesamthochschule, Hagen D 58084, Germany

Abstract

In 1997, J. A. Fridy gave conditions for noninclusion of ordinary and of absolute summability domains. In the present note, these conditions are interpreted in a natural topological context thus giving new proofs and also explaining why one of these conditions is too weak. Also an open question posed in Fridy's paper is answered.