Sum by converting to a difference equation and solving that difference equation:
Express as a sum of falling factorials.
Use this result to find:
Sum by parts:
Find the difference (with respect to n- 1 point each)
Not what I was expecting, but correct.
(n+1)! - n ! =
(n+1) n! - n! = n n!
Since = + , we get for the difference.
Find an anti -difference: (with respect to n - 2 points each)