4d * (16d^2 - 4dc^4 + c^8)+c^4*(16d^2 - 4dc^4 + c^8) =
64d^3 - 16c^4d^2 + 4c^8d + 16c^4d^2-4c^8d+c =
64d^3 + 4c^8d - 4c^8d + c^12 =
64d^3 + c^12 =
