Javascript Primality Tester
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Algorithm
The above prime checker performs 50 rounds of a Miller-Rabin primality test, a fast probabilistic
prime checking algorithm. The algorithm is guaranteed not to produce false negatives - if a number
is declared composite, then it is definitely composite. However, with astronomically small probability,
a false positive may occur - it is possible (but extraordinarily unlikely) that a number declared prime
is actually composite.
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