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# A combinatorial identity (teaser?)

$\sum_{k=1}^{n-1} H_{k}H_{n-k} \equiv 2\sum_{k=1}^{n-1} H_{k}\frac{n-k}{k+1}$

Try to prove it! If you want to know how I proved it, get this thread to hit 20 replies saying "Asuka best grill :^)" and the question mark will go away ;)

($$H_{n} = \frac{1}{1}+\frac{1}{2}+\ldots+\frac{1}{n}$$)

Note by Jake Lai
2 years, 6 months ago

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The only question mark in your note is in the title.

- 2 years, 4 months ago

Rei best grill

- 2 years, 6 months ago

What shit taste ;c

- 2 years, 6 months ago

Likewise my friend

- 2 years, 6 months ago