Solve a differential equation using series expansions.
Given an ODE such as y″ Is it possible to get sage to display the solution in the from (at least the first few terms of the expansion) y=a_o\left(c_0+c_1x+c_2x^2+\dots\right) + a_1\left(d_0+d_1x+d_2x^2+\dots\right)
EDIT: I have made some progress, functional but it is not pretty. second attempt