First note that

is a regular singular point; in particular

is a pole of order 1 for

.
We seek a solution of the form

where

is to be determined. Differentiating, we have


and substituting into the ODE gives






The indicial polynomial,

, has roots at

and

. Because these roots are separated by an integer, we have to be a bit more careful, but we'll get back to this later.
When

, we have the recurrence

valid for

. When

, with

, we find




and so on, with a general pattern of

Similarly, when

for

, we find




and so on, with the general pattern

So the first indicial root admits the solution



which you can recognize as the power series for

and

.
To be more precise, the second series actually converges to

, which doesn't satisfy the ODE. However, remember that the indicial equation had two roots that differed by a constant. When

, we may seek a second solution of the form

where

. Substituting this into the ODE, you'll find that

, and so we're left with


Expanding

, you'll see that all the terms

with

in the expansion of this new solutions are already accounted for, so this new solution really only adds one fundamental solution of the form

. Adding this to

, we end up with just

.
This means the general solution for the ODE is