ISL 2020 N6
For a positive integer , let be the number of positive divisors of , and let be the number of positive integers not exceeding which are coprime to . Does there exist a constant such that for all ? (Cyprus)
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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