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arXiv · 1011.1399

The boundary Carath\'{e}odory-Fej\'{e}r interpolation problem

Jim Agler·Zinaida A. Lykova·N. J. Young
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Abstract

We give an elementary proof of a solvability criterion for the {\em boundary Carath\'{e}odory-Fej\'{e}r problem}: given a point $x \in \R$ and, a finite set of target values, to construct a function $f$ in the Pick class such that the first few derivatives of $f$ take on the prescribed target values at $x$. We also derive a linear fractional parametrization of the set of solutions of the interpolation problem. The proofs are based on a reduction method due to Julia and Nevanlinna.

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Jim Agler, Zinaida A. Lykova, N. J. Young. 2010-11-05. The boundary Carath\'{e}odory-Fej\'{e}r interpolation problem. https://arxiv.org/abs/1011.1399

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