Can someone explain the comment 40.391?

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40.33: $x^2 y''+xf_1(x)y'+f_2(x)y=0$
where $f_1(x)$ and $f_2(x)$ are analytic at $x=0$.
I don't know how to relate frobenius solutions and the complex plane mentioned.This is from morris-tennenbaum ordinary DE