200n diagonals are drawn in a convex n-gon
Source: 239MO 2004, grade 8-9, problem 8, grade 10-11, problem 7
December 11, 2004
inductioncombinatorics unsolvedcombinatorics
Problem Statement
diagonals are drawn in a convex -gon. Prove that one of them intersects at least 10000 others.
proposed by D. Karpov, S. Berlov