Two weeks ago we featured a problem submitted by Sandeep S. In our opinion it was such a superlative problem, that everyone of all levels should get to see it.
Here is the problem:
Sandeep's Harmonic Sums
For each positive integer , let If for relatively prime positive integers and , find .
This problem is posed by Sandeep S.
Therefore the answer is .
The elegance of the solution blew us all away. Thanks Sandeep for such a cool problem!