Stability of Jamison sequences under certain perturbations

Journal article, 2019

An increasing sequence of positive integers (nk) is said to be Jamison if whenever T is a linear bounded operator on a complex separable Banach space, the following holds : 
sup||Tnk|| < ∞ ⇒ σp(T )∩S1 is countable
k

In this paper, we study certain perturbations on the set of Jamison sequences and prove a stability result.