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Journal of Applied Analysis 14 (2008), No. 2, 259--271 Copyright Heldermann Verlag 2008 Differential Polynomials Generated by Second Order Linear Differential Equations Benharrat Belaïdi Dept. of Mathematics, Laboratory of Pure and Applied Mathematics, University of Mostaganem, B. P. 227, Mostaganem, Algeria belaidi@univ-mosta.dz Abdallah El Farissi Dept. of Mathematics, Laboratory of Pure and Applied Mathematics, University of Mostaganem, B. P. 227, Mostaganem, Algeria el.farissi.abdallah@caramail.com [Abstract-pdf] We study fixed points of solutions of the differential equation \begin{equation*} f^{{\prime \prime }}+A_{1}\left( z\right) f^{{\prime }}+A_{0}\left(z\right) f=0, \end{equation*} where $A_{j}\left( z\right) $ $\left( \not\equiv 0\right)$ $\left( j=0, 1 \right)$ are transcendental meromorphic functions with finite order. Instead of looking at the zeros of $f\left( z\right)-z$, we proceed to a slight generalization by considering zeros of $g\left(z\right)-\varphi \left( z\right)$, where $g$ is a differential polynomial in $f$ with polynomial coefficients, $\varphi$ is a small meromorphic function relative to $f$, while the solution $f$ is of infinite order. Keywords: Linear differential equations, meromorphic solutions, hyper order, exponent of convergence of the sequence of distinct zeros, hyper exponent of convergence of the sequence of distinct zeros. MSC: 34M10, 30D35 [ Fulltext-pdf (194 KB)] for subscribers only. |