Proceedings of the American Mathematical Society

The Schur algorithm and coefficient characterizations for generalized Schur functions

Author(s): Tiberiu Constantinescu; Aurelian Gheondea
Journal: Proc. Amer. Math. Soc. 128 (2000), 2705-2713.
MSC (1991): Primary 30C50, 47B50, 30E05
Posted: February 28, 2000
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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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Retrieve articles in Proceedings of the American Mathematical Society with MSC (1991): 30C50, 47B50, 30E05

Tiberiu Constantinescu
Affiliation: Department of Mathematics, University of Texas at Dallas, Richardson, Texas 75083-0688
Email: tiberiu@utdallas.edu

Aurelian Gheondea
Affiliation: Institutul de Matematica al Academiei Române, CP 1-764, 70700 Bucuresti, România
Email: gheondea@imar.ro

DOI: 10.1090/S0002-9939-00-05375-2
PII: S 0002-9939(00)05375-2
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
Posted: 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
Copyright of article: Copyright 2000, American Mathematical Society

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