2005 IMO Problems/Problem 2

Revision as of 11:19, 23 August 2020 by Pureswag (talk | contribs) (Created page with "Let <math>a_1, a_2, \dots</math> be a sequence of integers with infinitely many positive and negative terms. Suppose that for every positive integer <math>n</math> the numbers...")
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)

Let $a_1, a_2, \dots$ be a sequence of integers with infinitely many positive and negative terms. Suppose that for every positive integer $n$ the numbers $a_1, a_2, \dots, a_n$ leave $n$ different remainders upon division by $n$. Prove that every integer occurs exactly once in the sequence.