MathDB
min no of points, set of 1997 planes with at least 3 points (1997 Chile NMO P6)

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November 23, 2021
combinatorial geometrycombinatorics

Problem Statement

For each set CC of points in space, we designate by PCP_C the set of planes containing at least three points of CC. \bullet Prove that there exists CC such that ϕ(PC)=1997\phi (P_C) = 1997, where ϕ\phi corresponds to the cardinality. \bullet Determine the least number of points that CC must have so that the previous property can be fulfilled.