InverseSystem(I: IDEAL, D: INT): LIST of RINGELEM
/**/ use QQ[x,y,z]; /**/ InverseSystem(ideal(x^3+x*y*z), 3); [z^3, y*z^2, x*z^2, y^2*z, x^2*z, y^3, x*y^2, x^2*y, x^3 - 6*x*y*z]