Are you thinking of the sum of the first N natural numbers?

I've heard the legend/story that he (Guass) came up with this when he was somewhere between 10 and 15 years old (for the record, I might have come up with this when I was 10, but cartoons were more interesting than math then).

Anyway, it's S=N*(N+1)/2



FouRPlaY
Learning Perl or Going To Die Trying

In reply to RE: Re: Recursion by FouRPlaY
in thread Recursion by lolindrath

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