The gcd command finds the greatest common
divisor of two polynomials with coefficients in ℤ/pℤ (for prime
p). (See also Section 7.1.1 and Section 11.2.5.)
gcd takes two arguments:
P and Q, two polynomials with coefficients in
ℤ/pℤ (p must be prime).
gcd(P,Q) returns
the GCD of P and Q computed in ℤ/pℤ[x]
