source 2008 Bernstein-–Lange-–Rezaeian Farashahi
parameter sqrtd1
assume sqrtd1^2 = d1
appliesto xyz-1
compute W1 = X1 + Y1
compute E = (W1(W1 + Z1))^2
compute X3 = ((sqrtd1 W1 + X1)Z1 + X1^2)^2
compute Y3 = X3 + E
compute Z3 = E + d1(Z1^2)^2