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I have another question:

It says: Evaluate in closed form

n(sigma)i=1 (2^i - i^2)

(The n is above the sigma and the i=1 is below)

what i did so far is:

(sigma)2*2^i-1 (sigma)i^2

=(2(2^n -1)/2-1) - (n(n+1)(2n+1)/6)

now do I need to do something else to shorten this down... if so can someone help me with it...

THANKS!

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# Homework Help: Sigma-evaluate in closed form

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