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The Schur algorithm and coefficient characterizations for generalized Schur functions

Authors: Tiberiu Constantinescu and Aurelian Gheondea
Journal: Proc. Amer. Math. Soc. 128 (2000), 2705-2713
MSC (1991): Primary 30C50, 47B50, 30E05
Published electronically: February 28, 2000
MathSciNet review: 1670430
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Abstract | References | Similar Articles | Additional Information


In this paper we analyze the existence of a Schur algorithm and obtain coefficient characterizations for the functions in a generalized Schur class. An application to an interpolation problem of Carathéodory type raised by M.G. Krein and H. Langer is indicated.

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Additional Information

Tiberiu Constantinescu
Affiliation: Department of Mathematics, University of Texas at Dallas, Richardson, Texas 75083-0688

Aurelian Gheondea
Affiliation: Institutul de Matematică al Academiei Române, CP 1-764, 70700 Bucureşti, România

Keywords: Schur functions, Schur algorithm, coefficient characterization, Carath\'eodory problem, Kre\u\i n space
Received by editor(s): March 30, 1998
Received by editor(s) in revised form: October 29, 1998
Published electronically: February 28, 2000
Additional Notes: The second author’s research was partially supported by the Ministry of Research and Technology of Romania grant 4022GR/1998.
Communicated by: David R. Larson
Article copyright: © Copyright 2000 American Mathematical Society