K1021 :b^5 c^7 x^2 y-a b^3 c^8 x^2 y-a^5 c^7 x y^2+a^3 b c^8 x y^2+a b^8 c^3 x^2 z-b^7 c^5 x^2 z-a^8 b c^3 y^2 z+a^7 c^5 y^2 z+a^5 b^7 x z^2-a^3 b^8 c x z^2-a^7 b^5 y z^2+a^8 b^3 c y z^2 = 0