I need to solve the differential equation \(\displaystyle y'-x^2-e^y=0\) using series, with initial conditions x=0 and y=0.

My problem is \(\displaystyle e^y\). I know what I could have done with \(\displaystyle e^x\) (replace \(\displaystyle e^x\), \(\displaystyle y\) and \(\displaystyle y'\) par their series in the differential equation) ... but what can I do with \(\displaystyle e^y\) ??

Thanks to everybody,