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ArticleOriginal scientific text

Title

The stability radius of an operator of Saphar type

Authors 1

Affiliations

  1. Mathematisches Institut I, Universität Karlsruhe, Postfach 6980, D-76128 Karlsruhe, Germany

Abstract

A bounded linear operator T on a complex Banach space X is called an operator of Saphar type if its kernel is contained in its generalized range ⋂n=1∞Tn(X) and T is relatively regular. For T of Saphar type we determine the supremum of all positive numbers δ such that T - λI is of Saphar type for |λ| < δ.

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Studia Mathematica
1995/113/2
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Pages:
169-175
Main language of publication
English
Received
1994-03-08
Accepted
1994-10-18
Published
1995
Exact and natural sciences