Problems with meeting people!
Find all positive integers $n < 10^{100}$ for which simultaneously $n$ divides $2^n$, $n-1$ divides $2^n - 1$, and $n-2$ divides $2^n - 2$.Determine all solutions in non-zero integers $a$ and ...
Computational Geo
Some Geometry Problems for everyone to try!
These problems are INMO~ish level. So trying this would be a good practice for INMO! Let $ABCD$ be a quadrilateral. Let $M,N,P,Q$ be the midpoints of sides $AB,BC,CD,DA$. Prove that $MNPQ$ ...
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