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# Sum (r(r^2-1))^-1 watch

1. (Original post by It'sPhil...)
To generalise the result try: Prove that for every integer k, with k>1

(sum over r >= 1) 1 / [r(r + 1)(r + 3)...(r + k)] = 1/(k!k)
That's a neat result!
You certainly no longer need a script or computer program
2. (Original post by It'sPhil...)
To generalise the result try: Prove that for every integer k, with k>1

(sum over r >= 1) 1 / [r(r + 1)(r + 3)...(r + k)] = 1/(k!k)
Hmm, no one's done it yet.
See below.
Attached Images
3. neat_sum.pdf (41.9 KB, 271 views)

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