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Timeline for A balls-and-colours problem

Current License: CC BY-SA 2.5

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Jan 21, 2011 at 21:24 history edited David E Speyer CC BY-SA 2.5
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Oct 14, 2010 at 0:08 history edited David E Speyer CC BY-SA 2.5
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Oct 13, 2010 at 21:41 comment added JBL Barring arithmetic errors, we can also rewrite your final expression as $\frac{(2j - 1)(n - 1)(n - j)}{n} - (n - 1)(n - j) \sum_{k = 1}^{j - 1} \frac{1}{n - k}$, which does indeed look fairly simple in terms of harmonic numbers, as A. Rex remembered.
Oct 13, 2010 at 19:16 history edited David E Speyer CC BY-SA 2.5
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Oct 13, 2010 at 18:49 history answered David E Speyer CC BY-SA 2.5