Number theoryDifficulty 7.0National Olympiad, round 2Find the answerUnited Kingdom
A sequence of positive integers an begins with a1=a and a2=b for positive integers a and b. Subsequent terms in the sequence satisfy the following two rules for all positive integers n: a2n+1=a2na2n−1,a2n+2=a2n+1+4. Exactly m of the numbers a1,a2,a3,…,a2022 are square numbers. What is the maximum possible value of m? Note that m depends on a and b, so the maximum is over all possible choices of a and b.
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