Differential Equation - Series - Recurrence Relation

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1. (16+x2)-xy'+32y=0

Seek a power series solution for the given differential equation about the given point x0 find the recurrence relation.
So I used y=∑Anxn , found y' and y''
then I substituted it into the original equation, distributed, made all x to the n power equal to xn, made the indexes 0, and added them all up.

Then I solved for an+2 and got:

(an-32an-ann(n-1))/(16(n+2)(n+1))=an+2


The question asks for for the recurrence relation in the form of a2k+2 and a2k+3
which are supposed to be the recurrence relation for even and odd terms.

How do I put it into that format? I'm just not sure where to go from this point. Also can someone even verify if I did the first part of obtaining an+2 correctly?
 
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Picture of attempted solution
 
Never mind, I figured out the question. You can just substitute 2n+1 and 2n into all n's to get odd and even terms respectively.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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