Prove that the sequence 1967, 19671967, 196719671967,... contains an element that is divisible by 1969.
thanx
Yes man the pigeonhole is used! in term of remainders,
Try to look at this link A Walk Through Combinatorics: An ... - Google Ricerca Libri
The first chapter is about this principle and you can find a more detailed proof reletaed to this problem. It is the first of them. page 2.
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