yes...this should be simple algebra for someone dealing with series. and what does this have to do with the ratio test?

do you mean ?I have to use the ratio test to evaluate n2/(2n-1)! where n=1 for an infinite series...exam in a few hrs!

if so, we want to see if

if so, the series converges absolutely

by the way, what you wanted was 2(n + 1) - 1 = 2n + 1, not what you said before