a, b, c, d, 
4*a^2+2*a*b-2*a*c-5*a*d+9*b^2+6*b*c-3*b*d+7*c^2-6*c*d+3*d^2+7*a+5*b+7*c+9*d+5
8*a^2+9*a*b-3*a*c+9*a*d+6*b^2-7*b*c+9*b*d-6*c^2-7*c*d-2*d^2+8*a+4*b+8*c-4*d+2
5*a^2+2*a*b-7*a*c+5*a*d+7*b^2-8*b*c-4*b*d+7*c^2+2*c*d+8*d^2-7*a-7*b-8*c+3*d+8
2*a^2+9*a*b-7*a*c+5*a*d-4*b^2-5*b*c+3*b*d-4*c^2-5*c*d+7*d^2+4*a+6*b-9*c-5*d+2
