1. The problem statement, all variables and given/known data Hey all. I'm being asked to find the radius and interval of convergence for the series from 1 to infinity: x^n/(1*3*5...(2n-1)) I have a feeling this is pretty straight forward (just apply the ratio test etc...), but my trouble lies in defining the denominator. Something to do with factorials? How do I get something to represent 1*3*5 all the way to *(2n-1)?