Abstract
The aim of this paper is to consider certain conditions on the coefficient A of the differential equation f″ + Af = 0 in the unit disc which place all normal solutions f in the union of Hardy spaces or result in the zero-sequence of each non-trivial solution being uniformly separated. The conditions on the coefficient are given in terms of Carleson measures.
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Supported by the Academy of Finland #258125 and #286877.
Supported in part by the grants MTM2014-51824-P, MTM2017-85666-P, and 2014SGR 75.
Supported in part by the Academy of Finland #268009, by the Faculty of Science and Forestry of University of Eastern Finland #930349, and by the grant MTM2011-26538.
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Gröhn, J., Nicolau, A. & Rättyä, J. Mean growth and geometric zero distribution of solutions of linear differential equations. JAMA 134, 747–768 (2018). https://doi.org/10.1007/s11854-018-0024-0
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DOI: https://doi.org/10.1007/s11854-018-0024-0