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Closed Closure (Posted on 2011-04-28) Difficulty: 3 of 5
Determine, with proof, the closed form of following expression in terms of n

Σj=1 to n  j2*(j+1)*(nCj)

See The Solution Submitted by K Sengupta    
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The closed form | Comment 2 of 3 |

Charlie, (2(n+1)^3-(n+1)^2+5n^2-1)*2^n/16 (equivalently,(n^3+5n^2+2n)*2^n/8)  solves for all n in your list.

Does this count as 'proof'?

Edited on April 29, 2011, 7:25 am
  Posted by broll on 2011-04-29 06:32:58

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