Call a pair of integers $(a,b)$ primitive if there exists a positive integer $\ell$ such that $(a+bi)^\ell$ is real. Find the smallest positive integer $n$ such that less than $1\%$ of the pairs $(a, b)$ with $0 \le a, b \le n$ are primitive.

Let's think step by step and output the final answer within \boxed{}.
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