x^4 - x^3 + x^2 - x + 1 x^4 - x^3 + 2*x - 1 x^4 - x^3 + x^2 + x + 1 x^4 - x^3 + x^2 + 4*x - 4 x^4 + 3*x^2 + 16 x^4 - x^3 - 14*x^2 + 14*x + 31 x^4 - 2*x^3 + 4*x^2 - 3*x + 16