I took a crypto class at the University of Minnesota. We covered a neat algorithm that can be found here. If I remember correctly, it's O(log(n)). You should be able to extend it to use Math::BigInt objects should you desire.

thor

In reply to Re: The Exponentiation of (not-so) Large Primes by thor
in thread The Exponentiation of (not-so) Large Primes by titivillus

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