Is R^1 equal to R, and if not, can they be considered isomorphic? Also, is there any meaning to R^n where n does not equal an integer greater than 0?
Is the following series converges or diverges: [math]\sum_ {r=0} ^ {r=n-1} \frac {r(r+1) (n-2)! } {(n-1) ^ {r} (n-r-1)! }[/math]?