In this paper, we investigate the limit points set of surjective and approximate point spectra of upper triangular operator matrices M C = µ A C 0 B ¶. We prove that σ * (M C) ∪ W = σ * (A) ∪ σ * (B) where W is the union of certain holes in σ * (M C), which happen to be subsets of σ lgD (B) ∩ σ rgD (A), σ * ∈ {σ lgD , σ rgD } are the limit points set of surjective and approximate point spectra. Furthermore, several sufficient conditions for σ * (M C) = σ * (A) ∪ σ * (B) holds for every C ∈ B(Y, X) are given.
In this paper, we investigate the classes of operators as class of generalized Drazin Riesz operators. We give some results for these classes throught localized single valued extension property (SVEP). Some applications are given.
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