- With GaussianIntegers->False, factorization is done over the ordinary ring of integers .
- With GaussianIntegers->True, factorization is done over the ring of integers with i adjoined .
- The Gaussian primes used when GaussianIntegers->True are chosen to have both real and imaginary parts positive.
- The first entry in the list given by FactorInteger with GaussianIntegers->True may be or -I.
Introduced in 1991