  In his paper Almost-Primes Represented by Quadratic Polynomials, Iwaniec
proved that the polynomial n^2 + 1 takes on values with at most two prime
factors (counted with multiplicity) infinitely often. He states that "in order
to avoid technical complications, we shall restrict our proof to the polynomial
n^2 + 1.". In this exposition, we follow Iwaniec's proof and show that for any
irreducible quadratic polynomial G(n) (satisfying some obviously necessary
hypotheses), G(n) has at most two prime factors for infinitely many values of
n.
