Strongly Cyclic and Strongly Irreducible Decomposition
纪友清, 韩黎明 · 东北数学：英文版 · 2001
Let W be an injective unilateral weighted shift, and let W^(n) be the orthogonal direct sum of n copies of W. In this paper, we prove that, if the commutant of W is strictly cyclic, then W^(n) has a unique (SI) decomposition with respect to similarity for every natural number n.