On Positive Quadratic Hyponormality of a Unilateral Weighted Shift with Recursively Generated by Five Weights

摘要

Let 1 a b c d and α ^ 5 : = 1 , a , b , c , d ∧ be a weighted sequence that is recursively generated by five weights 1 , a , b , c , d . In this paper, we give sufficient conditions for the positive quadratic hyponormalities of W α x and W α y , x , with α x : x , α ^ 5 and α y , x : y , x , α ^ 5 .