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The Nevanlinna-Pick theorem and a non-positive definite matrix

Published online by Cambridge University Press:  17 April 2009

Takahiko Nakazi
Takahiko Nakazi
Affiliation:
Department of Mathematics Faculty of Science (General Education), Hokkaido University, Sapporo 060, Japan
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Let {zj} be an interpolation sequence in the open unit disc and {wj} a bounded sequence. In this note, it is shown that there is a function F in H∞ + C satisfying ‖F‖ ≤ 1 and as j → ∞ if and only if there exists a compact matrix [tij] such that on where .

Type
Research Article
Information
Bulletin of the Australian Mathematical Society , Volume 36 , Issue 3 , December 1987 , pp. 361 - 365
Copyright
Copyright © Australian Mathematical Society 1987

References

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