• Sanchez-Perales, Salvador (Facultad de Ciencias Fisico-Matematicas, BUAP) ;
  • Djordjevic, Slavissa V. (Facultad de Ciencias Fisico-Matematicas, BUAP)
  • Received : 2010.07.20
  • Published : 2011.11.30


In this note we give conditions for continuity of spectrum, approximative point spectrum and defect spectrum on the set $\{T\}+\mathcal{K}(X)$, where $T{\in}\mathcal{B}(X)$ and $\mathcal{K}(X)$ is the set of compact operators.


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