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Linear Differential Equations with Solutions in the Dirichlet Type Subspace of the Hardy Space

Published online by Cambridge University Press:  11 January 2016

J. Heittokangas
Affiliation:
University of Joensuu, Mathematics, P.O. Box 111, FI-80101 Joensuu, Finland, janne.heittokangas@joensuu.fi
R. Korhonen
Affiliation:
University of Joensuu, Mathematics, P.O. Box 111, FI-80101 Joensuu, Finland, risto.korhonen@joensuu.fi
J. Rättyä
Affiliation:
University of Joensuu, Mathematics, P.O. Box 111, FI-80101 Joensuu, Finland, jouni.rattya@joensuu.fi
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Abstract

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Sufficient conditions for the analytic coefficients of the linear differential equation

are found such that all solutions belong to a given -space, or to the Dirichlet type subspace Dp of the classical Hardy space Hp, where 0 < p ≤ 2. For 0 < q < ∞, the space consists of those functions f, analytic in the unit disc D, for which |f(z)|(1 – |z|2)q is uniformly bounded in D, and fDp if the integral ∫D |f′(z)|p(1 – |z|2)p–1z converges.

Keywords

Type
Research Article
Copyright
Copyright © Editorial Board of Nagoya Mathematical Journal 2007

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