There are \(X\) possibilities for the units digit of a perfect square when it is represented in base \(N.\) Compute the last three digits of \(X\) (in base 10).
Details and Assumptions:
We are talking about \(3, 5, 7, 11, 13\) in their decimal representations.
You might want to use the fact that \(3, 5, 7, 11, 13\) are all primes.
Your answer seems reasonable.
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