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Approximation by semi-Fredholm operators

Author: Fernando Galaz-Fontes
Journal: Proc. Amer. Math. Soc. 120 (1994), 1219-1222
MSC: Primary 47A58; Secondary 47A53
MathSciNet review: 1197536
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Abstract: We present a simple approach for calculating some known distances from a bounded operator defined on a separable Hilbert space to certain sets related to semi-Fredholm operators.

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Keywords: Semi-Fredholm operator, index, injective operator, surjective operator, essential minimum modulus
Article copyright: © Copyright 1994 American Mathematical Society

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