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LOCALISATION OF LINEAR DIFFERENTIAL EQUATIONS IN THE UNIT DISC BY A CONFORMAL MAP

Published online by Cambridge University Press:  15 October 2015

JUHA-MATTI HUUSKO*
Affiliation:
Department of Physics and Mathematics, University of Eastern Finland, P.O. Box 111, 80101 Joensuu, Finland email juha-matti.huusko@uef.fi
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Abstract

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We obtain lower bounds for the growth of solutions of higher order linear differential equations, with coefficients analytic in the unit disc of the complex plane, by localising the equations via conformal maps and applying known results for the unit disc. As an example, we study equations in which the coefficients have a certain explicit exponential growth at one point on the boundary of the unit disc and consider the iterated $M$-order of solutions.

Type
Research Article
Copyright
© 2015 Australian Mathematical Publishing Association Inc. 

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