K761 :

 a*b*c^3*x^2*y + b^2*c^3*x^2*y - b*c^4*x^2*y - a^2*c^3*x*y^2 - a*b*c^3*x*y^2 + a*c^4*x*y^2 - a*b^3*c*x^2*z + b^4*c*x^2*z - b^3*c^2*x^2*z - a^4*c*y^2*z + a^3*b*c*y^2*z + a^3*c^2*y^2*z + 
     a^2*b^3*x*z^2 - a*b^4*x*z^2 + a*b^3*c*x*z^2 + a^4*b*y*z^2 - a^3*b^2*y*z^2 - a^3*b*c*y*z^2 = 0