On non-normal solutions of linear differential equations
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Abstract:
Normality arguments are applied to study the oscillation of solutions of $f''+Af=0$, where the coefficient $A$ is analytic in the unit disc $\mathbb {D}$ and $\sup _{z\in \mathbb {D}} (1-|z|^2)^2|A(z)| < \infty$. It is shown that such a differential equation may admit a non-normal solution having prescribed uniformly separated zeros.References
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Additional Information
- Janne Gröhn
- Affiliation: Department of Physics and Mathematics, University of Eastern Finland, P.O. Box 111, FI-80101 Joensuu, Finland
- MR Author ID: 943256
- Email: janne.grohn@uef.fi
- Received by editor(s): February 2, 2016
- Received by editor(s) in revised form: May 13, 2016
- Published electronically: September 8, 2016
- Additional Notes: The author was supported in part by the Academy of Finland, projects #258125 and #286877.
- Communicated by: Stephan Ramon Garcia
- © Copyright 2016 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 145 (2017), 1209-1220
- MSC (2010): Primary 34C10
- DOI: https://doi.org/10.1090/proc/13292
- MathSciNet review: 3589320