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Factorizations of outer functions and extremal problems

Published online by Cambridge University Press:  20 January 2009

Takahiko Nakazi
Affiliation:
Department of Mathematics Faculty of Science Hokkaido University Sapporo 060 Japan
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Abstract

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The author has proved that an outer function in the Hardy space H1 can be factored into a product in which one factor is strongly outer and the other is the sum of two inner functions. In an endeavor to understand better the latter factor, we introduce a class of functions containing sums of inner functions as a special case. Using it, we describe the solutions of extremal problems in the Hardy spaces Hp for 1≦p<∞.

Type
Research Article
Copyright
Copyright © Edinburgh Mathematical Society 1996

References

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