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A comment on Project Euler. Parent comment

Re:Project Euler by tomjakubowski on Monday December 11, 2017 @01:40AM (#15895521)
Isn't sum(1...n) - sum(1...n-1) just n? (1+2+3+4+5 - (1+2+3+4) = 5). That should be a +, right?

This is an awesome visualization, by the way.

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Re:Project Euler by nhebb on Monday December 11, 2017 @01:51AM (#15895556)
> Isn't sum(1...n) - sum(1...n-1) just n?

Yes. I meant n^2 = sum(1..n-1) + sum(1..n).

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