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162

Part of 1949 Moscow Mathematical Olympiad

Problems(1)

MMO 162 Moscow MO 1949 foursomes of 4n a geometric progression

Source:

7/20/2019
Given a set of 4n4n positive numbers such that any distinct choice of ordered foursomes of these numbers constitutes a geometric progression. Prove that at least 44 numbers of the set are identical.
geometric progressioncombinatoricsalgebrageometric sequence