Easy (beginner) sum problem:"need a summation variable"?

pepe
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My native language is not english but I try my best to make you understand the problem. I'd like to: from k=1 to n+1 sum k^2

But when I try to solve it with sage, it gives me an error.

(k,n)=var('k,n') show(sum(k,k^2,1,n+1))

It has a problem with k^2. How to solve it?

Many thanks.

1 Answer

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sage: var('k,n'); sum(k^2, k, 1, n+1)
(k, n)
1/3*n^3 + 3/2*n^2 + 13/6*n + 1

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Asked: 2012-02-26 16:05:55 +0100

Seen: 2,820 times

Last updated: Feb 26 '12