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All-Russian Olympiad Regional Round
2004 All-Russian Olympiad Regional Round
10.4
10.4
Part of
2004 All-Russian Olympiad Regional Round
Problems
(1)
N <= (n + 1)^2 points - All-Russian MO 2004 Regional (R4) 10.4
Source:
9/27/2024
N
≥
3
N \ge 3
N
≥
3
different points are marked on the plane. It is known that among pairwise distances between marked points there are not more than
n
n
n
different distances. Prove that
N
≤
(
n
+
1
)
2
N \le (n + 1)^2
N
≤
(
n
+
1
)
2
.
geometry
combinatorics
combinatorial geometry