A note on Tauberian operators

Abstract

In this note we prove the existence of operators which are not Tauberian even though they satisfy properties about restrictions being Tauberian. The operators are defined on Banach spaces which contain a somewhat reflexive, non-reflexive subspace. This gives an answer to a question proposed by R. Neidinger [1].

Keywords

• Tauberian operators
• and semi-Fredholm operators.