> When n > sqrt(MAXINT) the result of n*n would be
 > negative.

    It might appear negative Neil, but it is impossible for a square to be
anything but positive.

    j notation is used in engineering for complex numbers (or it was fifty
years ago when I studied physics and math at school). Mathematicians mostly
use i instead of j. It represents the imaginary number, the square root of
-1.

Best Wishes,
Bill.

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