In this paperwe characterize sequences of orthogonal polynomials on the
unit circle whose Carathéodory function satisfies a Riccati differential equation
with polynomial coefficients, in terms of matrix Sylvester differential
equations. For the particular case of semi-classical orthogonal polynomials
on the unit circle, it is derived a characterization in terms of first order linear
differential systems.info:eu-repo/semantics/publishedVersio
