>>660
http://www.wolframalpha.com/input/?i=Expand%5BSum%5B%28%281%2F6%29%28x%2Bx%5E2%2Bx%5E3%2Bx%5E4%2Bx%5E5%2Bx%5E6%29%29%5Ek%2C%7Bk%2C1%2C6%7D%5D%5D&;amp;dataset=