[ x^4 - x^3 - 36*x^2 - 91*x - 61, \ x^4 - 2*x^3 - 3*x^2 - 63*x + 540, \ x^4 - 15*x^2 + 1681, \ x^4 - x^3 + 1613*x^2 + 6505*x + 117018 ]