ISL 2020 N1
Given a positive integer , show that there exists a prime such that one can choose distinct integers such that divides for all . (South Africa)
Official text Transcription from NuminaMath olympiads, checked word for word against the official paper. Quoted with source.
Official text: IMO 2020 Shortlist booklet, page 12.
Solutions
Official solution Solution 1 by the IMO Problem Selection Committee
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