[ x^4 - x^3 - x^2 - 20*x + 48, \ x^4 - x^3 - 7*x^2 + 11*x + 3, \ x^4 + 35*x^2 + 144, \ x^4 - 2*x^3 - 4*x^2 + 5*x - 156 ]