Proceedings of the American Mathematical Society · 1973 · 11 citations · 1 references
Natural SciencesProperty LawSystems AnalysisOperator TheoryFredholm OperatorsFredholm TheoryOperator SpacesOperators
Let X, Y, Z be Banach spaces, and let T.X-+Yand S: Y^-Z be Fredholm operators. Let ind(r) denote the index of T. A short proof is given for the identity ind(57') = ind(S) + ind(7').
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