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On the growth of solutions of second order linear differential equations with extremal coefficients. (English) Zbl 1266.34140
The authors consider the second-order linear differential equation of the form $f''+A(z)f'+B(z)f = 0,$ where $$A$$ and $$B$$ are entire functions. The main result is that, if $$A$$ is extremal for Yang’s inequality, in the sense that the number of finite deficient values is equal to half of the number of Borel directions, and if the orders of $$A$$ and $$B$$ are not the same, then every non-trivial solution $$f$$ of the equation is of infinite order.

##### MSC:
 34M10 Oscillation, growth of solutions to ordinary differential equations in the complex domain 30D35 Value distribution of meromorphic functions of one complex variable, Nevanlinna theory
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##### References:
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