ISL-1999 N3

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sourav das
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ISL-1999 N3

Unread post by sourav das » Sun Apr 08, 2012 2:36 pm

Prove that there exists two strictly increasing sequences ($a_{n}$) and ($b_{n}$) such that $a_{n}(a_{n}+1)$ divides $b^{2}_{n}+1$ for every natural $n$.
You spin my head right round right round,
When you go down, when you go down down......
(-$from$ "$THE$ $UGLY$ $TRUTH$" )

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