Second Problem, IMAR Competition 2012
- Laurențiu Ploscaru
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- Membru din: Mie Mai 04, 2011 5:42 pm
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Second Problem, IMAR Competition 2012
Given an integer $n\ge 2$, compute the sum $\displaystyle\sum \dfrac{1}{pq}$ where the summation is over all coprime integers $p$ and $q$ such that $1\le p < q\le n$ and $p + q > n$.
People are strange when you're a stranger,
Faces look ugly when you're alone.
Women seem wicked when you're unwanted,
Streets are uneven when you're down.
Faces look ugly when you're alone.
Women seem wicked when you're unwanted,
Streets are uneven when you're down.