Dear Clinton,
all irreducible polynomials of degree n over GF(2) can be obtained by
factoring x^(2^n)+x, and keeping only factors of degree n:
sage: P. = GF(2)[]
sage: factor(x^(2^5)+x)
x * (x + 1) * (x^5 + x^2 + 1) * (x^5 + x^3 + 1) * (x^5 + x^3 + x^2 + x + 1) *
(x^5 + x^4 + x^2 + x + 1)
Is this what you are looking for?
sage: P. = GF(2)[]
sage: f = P.random_element(degree=31)
sage: f.is_irreducible()
False
sage: while f.degree() != 31 or f.is_irreducible() is False:
: f = P.random_element(degree=31)
:
sage: f.is_irreducible()
True
sage: f.degree()
31