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arXiv · 1604.07629

On a Simultaneous Approach to the Even and Odd Truncated Matricial Stieltjes Moment Problem II. An $α$-Schur-Stieltjes-type algorithm for sequences of holomorphic matrix-valued functions

Abstract

The main goal of this paper is to achieve a simultaneous treatment of the even and odd truncated matricial Stieltjes moment problems in the most general case. These results are generalizations of results of Chen and Hu [5,17] which considered the particular case $α=0$. Our approach is based on Schur analysis methods. More precisely, we use two interrelated versions of Schur-type algorithms, namely an algebraic one and a function-theoretic one. The algebraic version was worked out in a former paper of the authors. It is an algorithm which is applied to finite or infinite sequences of complex matrices. The construction and investigation of the function-theoretic version of our Schur-type algorithm is a central theme of this paper. This algorithm will be applied to relevant subclasses of holomorphic matrix-valued functions of the Stieltjes class. Using recent results on the holomorphicity of the Moore-Penrose inverse of matrix-valued Stieltjes functions, we obtain a complete description of the solution set of the moment problem under consideration in the most general situation.

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Bernd Fritzsche, Bernd Kirstein, Conrad Mädler. 2016-04-26. On a Simultaneous Approach to the Even and Odd Truncated Matricial Stieltjes Moment Problem II. An $α$-Schur-Stieltjes-type algorithm for sequences of holomorphic matrix-valued functions. https://arxiv.org/abs/1604.07629

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