So do the first few:

So we see that we can rewrite it like so:

So

To prove it:

So our formula is true for n=1

The next iteration will be 2(n+1) so multiply both sides by this:

So by induction, it is true.

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Does it give you an or ?

Also, can you use parenthases? I'm interpreting this as But I am not sure this is correct.