2 papers
math.FA2026
A Combinatorial Formula for Recursive Operator Sequences and Applications
Raul E. Curto, Abderrazzak Ech-charyfy, Kaissar Idrissi +1
We study sequences of bounded operators \((T_n)_{n \ge 0}\) on a complex separable Hilbert space \(\mathcal{H}\) that satisfy a linear recurrence relation of the form $$ T_{n+r} =…
math.FA2020
Jumping flatness and Aluthge transform of recursive weighted shifts
H. El Azhar, K. Idrissi, E. H. Zerouali
We devote this paper to Hamburger type weighted shifts. We give in particular an affirmative answer to a problem concerning subnormality of the Aluthge transform of Hamburger momen…