[ x^4 - 3*x^2 - 10*x + 28, \ x^4 - x^3 - 36*x^2 - 91*x - 61, \ x^4 - 37*x^2 + 900, \ x^4 - x^3 - 60*x^2 + 309*x - 452, \ x^4 - x^3 + 546*x^2 + 2237*x + 15653 ]