f(f(f(f(f(x,z),y),y),z),f(f(f(x,z),f(y,z)),x)) = z.
f(f(f(f(f(x,z),y),y),z),f(x,f(f(z,x),f(z,y)))) = z.
f(f(f(f(f(x,z),y),y),z),f(x,f(f(y,z),f(z,x)))) = z.
f(f(f(f(f(x,z),y),y),z),f(x,f(f(x,z),f(z,y)))) = z.
f(f(f(f(f(x,z),y),y),z),f(x,f(f(z,z),f(z,y)))) = z.
f(f(f(f(f(x,z),y),y),z),f(x,f(f(z,z),f(z,x)))) = z.
f(f(f(f(x,f(z,y)),x),z),f(f(f(y,z),f(y,z)),y)) = z.
f(f(f(f(x,f(y,z)),x),z),f(f(f(y,z),f(y,z)),y)) = z.
f(f(f(f(x,f(z,y)),x),z),f(f(f(y,z),f(x,z)),y)) = z.
f(f(f(f(x,f(z,y)),x),z),f(f(f(x,z),f(y,z)),y)) = z.
f(f(f(f(x,f(y,z)),x),z),f(f(f(y,z),f(x,z)),y)) = z.
f(f(f(f(x,f(y,z)),x),z),f(f(f(x,z),f(y,z)),y)) = z.
f(f(f(f(x,f(z,y)),x),z),f(y,f(f(y,z),f(z,y)))) = z.
f(f(f(f(x,f(z,y)),x),z),f(y,f(f(z,y),f(z,x)))) = z.
f(f(f(f(x,f(y,z)),x),z),f(y,f(f(z,y),f(z,x)))) = z.
f(f(f(f(x,f(y,z)),x),z),f(y,f(f(z,x),f(z,y)))) = z.
f(f(f(f(x,f(y,z)),x),z),f(y,f(f(x,z),f(z,y)))) = z.
f(f(f(f(x,f(z,y)),x),z),f(y,f(f(z,z),f(z,x)))) = z.
f(f(f(f(x,f(y,z)),x),z),f(y,f(f(z,z),f(z,y)))) = z.
f(f(f(f(x,f(y,z)),x),z),f(y,f(f(z,z),f(z,x)))) = z.
f(f(f(f(x,z),f(z,x)),x),f(z,f(f(f(z,x),y),y))) = z.
f(f(f(f(x,z),f(z,y)),y),f(z,f(f(f(z,y),x),x))) = z.
f(f(f(f(x,z),f(z,y)),y),f(z,f(f(f(y,z),x),x))) = z.
f(f(f(f(x,z),f(z,y)),x),f(z,f(f(f(z,x),y),y))) = z.
f(f(f(f(x,z),f(z,y)),x),f(z,f(f(f(x,z),y),y))) = z.
f(f(f(f(x,z),f(y,z)),y),f(z,f(f(f(z,y),x),x))) = z.
f(f(f(f(x,z),f(y,z)),y),f(z,f(f(f(y,z),x),x))) = z.
f(f(f(f(x,z),f(y,z)),x),f(z,f(f(f(x,z),y),y))) = z.
f(f(f(f(x,z),f(z,z)),y),f(z,f(f(f(z,y),x),x))) = z.
f(f(f(f(x,z),f(z,z)),y),f(z,f(f(f(y,z),x),x))) = z.
f(f(f(f(x,z),f(z,x)),x),f(z,f(f(y,f(z,x)),y))) = z.
f(f(f(f(x,z),f(z,y)),y),f(z,f(f(x,f(y,z)),x))) = z.
f(f(f(f(x,z),f(z,y)),x),f(z,f(f(y,f(x,z)),y))) = z.
f(f(f(f(x,z),f(y,z)),y),f(z,f(f(x,f(z,y)),x))) = z.
f(f(f(f(x,z),f(y,z)),y),f(z,f(f(x,f(y,z)),x))) = z.
f(f(f(f(x,z),f(y,z)),x),f(z,f(f(y,f(z,x)),y))) = z.
f(f(f(f(x,z),f(z,z)),y),f(z,f(f(x,f(z,y)),x))) = z.
f(f(f(f(x,z),f(z,z)),y),f(z,f(f(x,f(y,z)),x))) = z.
f(f(f(f(x,z),f(z,y)),x),f(z,f(y,f(f(z,x),y)))) = z.
f(f(f(f(x,z),f(y,z)),y),f(z,f(x,f(f(z,y),x)))) = z.
f(f(f(f(x,z),f(y,z)),y),f(z,f(x,f(f(y,z),x)))) = z.
f(f(f(f(x,z),f(y,z)),x),f(z,f(y,f(f(z,x),y)))) = z.
f(f(f(f(x,z),f(z,z)),y),f(z,f(x,f(f(z,y),x)))) = z.
f(f(f(f(x,z),f(z,z)),y),f(z,f(x,f(f(y,z),x)))) = z.
f(f(f(f(x,z),f(z,z)),x),f(z,f(y,f(f(z,x),y)))) = z.
f(f(f(f(x,z),f(z,y)),x),f(z,f(y,f(y,f(z,x))))) = z.
f(f(f(f(x,z),f(y,z)),y),f(z,f(x,f(x,f(z,y))))) = z.
f(f(f(f(x,z),f(z,z)),y),f(z,f(x,f(x,f(z,y))))) = z.
f(f(f(f(x,z),f(z,z)),x),f(z,f(y,f(y,f(z,x))))) = z.
f(f(f(x,f(f(z,y),x)),z),f(f(f(y,z),f(y,z)),y)) = z.
f(f(f(x,f(f(y,z),x)),z),f(f(f(y,z),f(y,z)),y)) = z.
f(f(f(x,f(f(z,y),x)),z),f(f(f(x,z),f(y,z)),y)) = z.
f(f(f(x,f(f(y,z),x)),z),f(f(f(y,z),f(x,z)),y)) = z.
f(f(f(x,f(f(y,z),x)),z),f(f(f(x,z),f(y,z)),y)) = z.
f(f(f(x,f(f(y,z),x)),z),f(y,f(f(y,z),f(z,y)))) = z.
f(f(f(x,f(f(z,y),x)),z),f(y,f(f(z,y),f(z,x)))) = z.
f(f(f(x,f(f(z,y),x)),z),f(y,f(f(y,z),f(z,x)))) = z.
f(f(f(x,f(f(z,y),x)),z),f(y,f(f(x,z),f(z,y)))) = z.
f(f(f(x,f(f(y,z),x)),z),f(y,f(f(z,y),f(z,x)))) = z.
f(f(f(x,f(f(y,z),x)),z),f(y,f(f(z,x),f(z,y)))) = z.
f(f(f(x,f(f(z,y),x)),z),f(y,f(f(z,z),f(z,x)))) = z.
f(f(f(x,f(f(y,z),x)),z),f(y,f(f(z,z),f(z,x)))) = z.
f(f(f(x,f(x,f(z,y))),z),f(f(f(y,z),f(x,z)),y)) = z.
f(f(f(x,f(x,f(y,z))),z),f(f(f(y,z),f(x,z)),y)) = z.
f(f(f(x,f(x,f(y,z))),z),f(f(f(x,z),f(y,z)),y)) = z.
f(f(f(x,f(x,f(y,z))),z),f(y,f(f(y,z),f(z,y)))) = z.
f(f(f(x,f(x,f(z,y))),z),f(y,f(f(z,y),f(z,x)))) = z.
f(f(f(x,f(x,f(z,y))),z),f(y,f(f(z,x),f(z,y)))) = z.
f(f(f(x,f(x,f(z,y))),z),f(y,f(f(y,z),f(z,x)))) = z.
f(f(f(x,f(x,f(z,y))),z),f(y,f(f(x,z),f(z,y)))) = z.
f(f(f(x,f(x,f(y,z))),z),f(y,f(f(z,y),f(z,x)))) = z.
f(f(f(x,f(x,f(y,z))),z),f(y,f(f(x,z),f(z,y)))) = z.
f(f(f(x,f(x,f(z,y))),z),f(y,f(f(z,z),f(z,x)))) = z.
f(f(f(x,f(x,f(y,z))),z),f(y,f(f(z,z),f(z,x)))) = z.
f(f(x,f(f(z,x),f(z,x))),f(z,f(f(f(x,z),y),y))) = z.
f(f(x,f(f(z,y),f(z,x))),f(z,f(f(f(z,x),y),y))) = z.
f(f(x,f(f(z,y),f(z,x))),f(z,f(f(f(x,z),y),y))) = z.
f(f(x,f(f(z,x),f(z,y))),f(z,f(f(f(z,x),y),y))) = z.
f(f(x,f(f(z,x),f(z,x))),f(z,f(f(y,f(z,x)),y))) = z.
f(f(x,f(f(z,x),f(z,x))),f(z,f(f(y,f(x,z)),y))) = z.
f(f(x,f(f(z,y),f(z,x))),f(z,f(f(y,f(z,x)),y))) = z.
f(f(x,f(f(z,x),f(z,y))),f(z,f(f(y,f(z,x)),y))) = z.
f(f(x,f(f(z,x),f(z,y))),f(z,f(f(y,f(x,z)),y))) = z.
f(f(x,f(f(z,x),f(z,x))),f(z,f(y,f(f(z,x),y)))) = z.
f(f(x,f(f(z,x),f(z,x))),f(z,f(y,f(f(x,z),y)))) = z.
f(f(x,f(f(z,y),f(z,x))),f(z,f(y,f(f(z,x),y)))) = z.
f(f(x,f(f(z,y),f(z,x))),f(z,f(y,f(f(x,z),y)))) = z.
f(f(x,f(f(z,x),f(z,y))),f(z,f(y,f(f(z,x),y)))) = z.
f(f(x,f(f(z,x),f(z,y))),f(z,f(y,f(f(x,z),y)))) = z.
f(f(x,f(f(z,y),f(z,x))),f(z,f(y,f(y,f(z,x))))) = z.
f(f(f(x,f(z,z)),z),f(f(f(f(y,x),x),f(y,z)),y)) = z.
f(f(f(x,f(z,z)),z),f(f(f(f(x,y),x),f(y,z)),y)) = z.
f(f(f(x,f(z,z)),z),f(f(f(x,f(y,x)),f(y,z)),y)) = z.
f(f(f(x,f(z,z)),z),f(f(f(y,z),f(f(y,x),x)),y)) = z.
f(f(f(x,f(z,z)),z),f(f(f(y,z),f(f(x,y),x)),y)) = z.
f(f(f(x,f(z,z)),z),f(f(f(y,z),f(x,f(y,x))),y)) = z.
f(f(f(x,f(z,z)),z),f(f(f(y,z),f(x,f(x,y))),y)) = z.
f(f(f(x,f(z,z)),z),f(y,f(f(f(x,y),x),f(z,y)))) = z.
f(f(f(x,f(z,z)),z),f(y,f(f(x,f(y,x)),f(z,y)))) = z.
f(f(f(x,f(z,z)),z),f(y,f(f(x,f(x,y)),f(z,y)))) = z.
f(f(f(x,f(z,z)),z),f(y,f(f(z,y),f(f(y,x),x)))) = z.
f(f(f(x,f(z,z)),z),f(y,f(f(z,y),f(f(x,y),x)))) = z.
f(f(f(x,f(z,z)),z),f(y,f(f(y,z),f(f(y,x),x)))) = z.
f(f(f(x,f(z,z)),z),f(y,f(f(y,z),f(f(x,y),x)))) = z.
f(f(f(x,f(z,z)),z),f(y,f(f(z,y),f(x,f(y,x))))) = z.
f(f(f(x,f(z,z)),z),f(y,f(f(z,y),f(x,f(x,y))))) = z.
f(f(f(x,z),z),f(f(f(z,y),f(x,z)),f(f(x,x),y))) = z.
f(f(f(x,z),z),f(f(f(y,z),f(x,z)),f(y,f(x,x)))) = z.
f(f(f(x,z),z),f(f(y,f(x,x)),f(f(z,y),f(z,x)))) = z.
f(f(f(x,z),z),f(f(y,f(x,x)),f(f(x,z),f(z,y)))) = z.
f(f(f(x,f(x,z)),x),f(z,f(z,f(f(y,x),f(u,x))))) = z.
f(f(f(x,f(x,z)),x),f(z,f(z,f(f(y,x),f(x,u))))) = z.
f(f(f(x,f(x,z)),x),f(z,f(z,f(f(x,y),f(u,x))))) = z.
f(f(f(x,f(x,z)),x),f(z,f(z,f(f(x,y),f(x,u))))) = z.
f(f(x,f(x,f(z,x))),f(z,f(z,f(f(y,x),f(u,x))))) = z.
f(f(x,f(x,f(z,x))),f(z,f(z,f(f(y,x),f(x,u))))) = z.
f(f(x,f(x,f(z,x))),f(z,f(z,f(f(x,y),f(u,x))))) = z.
f(f(x,f(x,f(z,x))),f(z,f(z,f(f(x,y),f(x,u))))) = z.
f(f(x,f(x,f(x,z))),f(z,f(z,f(f(y,x),f(u,x))))) = z.
f(f(x,f(x,f(x,z))),f(z,f(z,f(f(y,x),f(x,u))))) = z.
f(f(x,f(x,f(x,z))),f(z,f(z,f(f(x,y),f(u,x))))) = z.
f(f(x,f(x,f(x,z))),f(z,f(z,f(f(x,y),f(x,u))))) = z.
f(f(f(f(f(x,z),y),y),z),f(f(f(u,z),f(x,z)),x)) = z.
f(f(f(f(f(x,z),y),y),z),f(f(f(z,u),f(x,z)),x)) = z.
f(f(f(f(f(x,z),y),y),z),f(f(f(x,z),f(u,z)),x)) = z.
f(f(f(f(f(x,z),y),y),z),f(x,f(f(u,z),f(z,x)))) = z.
f(f(f(f(f(x,z),y),y),z),f(x,f(f(z,u),f(z,x)))) = z.
f(f(f(f(f(x,z),y),y),z),f(x,f(f(z,x),f(z,u)))) = z.
f(f(f(f(f(x,z),y),y),z),f(x,f(f(x,z),f(z,u)))) = z.
f(f(f(f(f(x,z),y),y),z),f(x,f(f(z,z),f(z,u)))) = z.
f(f(f(f(x,f(z,y)),x),z),f(f(f(u,z),f(y,z)),y)) = z.
f(f(f(f(x,f(z,y)),x),z),f(f(f(z,u),f(y,z)),y)) = z.
f(f(f(f(x,f(z,y)),x),z),f(f(f(y,z),f(u,z)),y)) = z.
f(f(f(f(x,f(y,z)),x),z),f(f(f(u,z),f(y,z)),y)) = z.
f(f(f(f(x,f(y,z)),x),z),f(f(f(z,u),f(y,z)),y)) = z.
f(f(f(f(x,f(y,z)),x),z),f(f(f(y,z),f(u,z)),y)) = z.
f(f(f(f(x,f(z,y)),x),z),f(y,f(f(u,z),f(z,y)))) = z.
f(f(f(f(x,f(z,y)),x),z),f(y,f(f(z,u),f(z,y)))) = z.
f(f(f(f(x,f(z,y)),x),z),f(y,f(f(z,y),f(z,u)))) = z.
f(f(f(f(x,f(z,y)),x),z),f(y,f(f(y,z),f(z,u)))) = z.
f(f(f(f(x,f(y,z)),x),z),f(y,f(f(u,z),f(z,y)))) = z.
f(f(f(f(x,f(y,z)),x),z),f(y,f(f(z,u),f(z,y)))) = z.
f(f(f(f(x,f(y,z)),x),z),f(y,f(f(z,y),f(z,u)))) = z.
f(f(f(f(x,f(y,z)),x),z),f(y,f(f(y,z),f(z,u)))) = z.
f(f(f(f(x,f(z,y)),x),z),f(y,f(f(z,z),f(z,u)))) = z.
f(f(f(f(x,f(y,z)),x),z),f(y,f(f(z,z),f(z,u)))) = z.
f(f(f(f(x,z),f(z,y)),y),f(z,f(f(f(z,y),u),u))) = z.
f(f(f(f(x,z),f(z,y)),y),f(z,f(f(f(y,z),u),u))) = z.
f(f(f(f(x,z),f(z,y)),x),f(z,f(f(f(z,x),u),u))) = z.
f(f(f(f(x,z),f(z,y)),x),f(z,f(f(f(x,z),u),u))) = z.
f(f(f(f(x,z),f(y,z)),y),f(z,f(f(f(z,y),u),u))) = z.
f(f(f(f(x,z),f(y,z)),y),f(z,f(f(f(y,z),u),u))) = z.
f(f(f(f(x,z),f(y,z)),x),f(z,f(f(f(z,x),u),u))) = z.
f(f(f(f(x,z),f(y,z)),x),f(z,f(f(f(x,z),u),u))) = z.
f(f(f(f(x,z),f(z,z)),y),f(z,f(f(f(z,y),u),u))) = z.
f(f(f(f(x,z),f(z,z)),y),f(z,f(f(f(y,z),u),u))) = z.
f(f(f(f(x,z),f(z,y)),y),f(z,f(f(u,f(z,y)),u))) = z.
f(f(f(f(x,z),f(z,y)),y),f(z,f(f(u,f(y,z)),u))) = z.
f(f(f(f(x,z),f(z,y)),x),f(z,f(f(u,f(z,x)),u))) = z.
f(f(f(f(x,z),f(z,y)),x),f(z,f(f(u,f(x,z)),u))) = z.
f(f(f(f(x,z),f(y,z)),y),f(z,f(f(u,f(z,y)),u))) = z.
f(f(f(f(x,z),f(y,z)),y),f(z,f(f(u,f(y,z)),u))) = z.
f(f(f(f(x,z),f(y,z)),x),f(z,f(f(u,f(z,x)),u))) = z.
f(f(f(f(x,z),f(y,z)),x),f(z,f(f(u,f(x,z)),u))) = z.
f(f(f(f(x,z),f(z,z)),y),f(z,f(f(u,f(z,y)),u))) = z.
f(f(f(f(x,z),f(z,z)),y),f(z,f(f(u,f(y,z)),u))) = z.
f(f(f(f(x,z),f(z,y)),y),f(z,f(u,f(f(z,y),u)))) = z.
f(f(f(f(x,z),f(z,y)),y),f(z,f(u,f(f(y,z),u)))) = z.
f(f(f(f(x,z),f(z,y)),x),f(z,f(u,f(f(z,x),u)))) = z.
f(f(f(f(x,z),f(z,y)),x),f(z,f(u,f(f(x,z),u)))) = z.
f(f(f(f(x,z),f(y,z)),y),f(z,f(u,f(f(z,y),u)))) = z.
f(f(f(f(x,z),f(y,z)),y),f(z,f(u,f(f(y,z),u)))) = z.
f(f(f(f(x,z),f(y,z)),x),f(z,f(u,f(f(z,x),u)))) = z.
f(f(f(f(x,z),f(y,z)),x),f(z,f(u,f(f(x,z),u)))) = z.
f(f(f(f(x,z),f(z,z)),y),f(z,f(u,f(f(z,y),u)))) = z.
f(f(f(f(x,z),f(z,z)),y),f(z,f(u,f(f(y,z),u)))) = z.
f(f(f(f(x,z),f(z,y)),y),f(z,f(u,f(u,f(z,y))))) = z.
f(f(f(f(x,z),f(z,y)),x),f(z,f(u,f(u,f(z,x))))) = z.
f(f(f(f(x,z),f(y,z)),y),f(z,f(u,f(u,f(z,y))))) = z.
f(f(f(f(x,z),f(y,z)),x),f(z,f(u,f(u,f(z,x))))) = z.
f(f(f(f(x,z),f(z,z)),y),f(z,f(u,f(u,f(z,y))))) = z.
f(f(f(x,f(f(z,y),x)),z),f(f(f(u,z),f(y,z)),y)) = z.
f(f(f(x,f(f(z,y),x)),z),f(f(f(z,u),f(y,z)),y)) = z.
f(f(f(x,f(f(z,y),x)),z),f(f(f(y,z),f(u,z)),y)) = z.
f(f(f(x,f(f(y,z),x)),z),f(f(f(u,z),f(y,z)),y)) = z.
f(f(f(x,f(f(y,z),x)),z),f(f(f(z,u),f(y,z)),y)) = z.
f(f(f(x,f(f(y,z),x)),z),f(f(f(y,z),f(u,z)),y)) = z.
f(f(f(x,f(f(z,y),x)),z),f(y,f(f(u,z),f(z,y)))) = z.
f(f(f(x,f(f(z,y),x)),z),f(y,f(f(z,u),f(z,y)))) = z.
f(f(f(x,f(f(z,y),x)),z),f(y,f(f(z,y),f(z,u)))) = z.
f(f(f(x,f(f(z,y),x)),z),f(y,f(f(y,z),f(z,u)))) = z.
f(f(f(x,f(f(y,z),x)),z),f(y,f(f(u,z),f(z,y)))) = z.
f(f(f(x,f(f(y,z),x)),z),f(y,f(f(z,u),f(z,y)))) = z.
f(f(f(x,f(f(y,z),x)),z),f(y,f(f(z,y),f(z,u)))) = z.
f(f(f(x,f(f(y,z),x)),z),f(y,f(f(y,z),f(z,u)))) = z.
f(f(f(x,f(f(z,y),x)),z),f(y,f(f(z,z),f(z,u)))) = z.
f(f(f(x,f(f(y,z),x)),z),f(y,f(f(z,z),f(z,u)))) = z.
f(f(f(x,f(x,f(z,y))),z),f(f(f(u,z),f(y,z)),y)) = z.
f(f(f(x,f(x,f(z,y))),z),f(f(f(z,u),f(y,z)),y)) = z.
f(f(f(x,f(x,f(z,y))),z),f(f(f(y,z),f(u,z)),y)) = z.
f(f(f(x,f(x,f(y,z))),z),f(f(f(u,z),f(y,z)),y)) = z.
f(f(f(x,f(x,f(y,z))),z),f(f(f(z,u),f(y,z)),y)) = z.
f(f(f(x,f(x,f(y,z))),z),f(f(f(y,z),f(u,z)),y)) = z.
f(f(f(x,f(x,f(z,y))),z),f(y,f(f(u,z),f(z,y)))) = z.
f(f(f(x,f(x,f(z,y))),z),f(y,f(f(z,u),f(z,y)))) = z.
f(f(f(x,f(x,f(z,y))),z),f(y,f(f(z,y),f(z,u)))) = z.
f(f(f(x,f(x,f(z,y))),z),f(y,f(f(y,z),f(z,u)))) = z.
f(f(f(x,f(x,f(y,z))),z),f(y,f(f(u,z),f(z,y)))) = z.
f(f(f(x,f(x,f(y,z))),z),f(y,f(f(z,u),f(z,y)))) = z.
f(f(f(x,f(x,f(y,z))),z),f(y,f(f(z,y),f(z,u)))) = z.
f(f(f(x,f(x,f(y,z))),z),f(y,f(f(y,z),f(z,u)))) = z.
f(f(f(x,f(x,f(z,y))),z),f(y,f(f(z,z),f(z,u)))) = z.
f(f(f(x,f(x,f(y,z))),z),f(y,f(f(z,z),f(z,u)))) = z.
f(f(x,f(f(z,y),f(z,x))),f(z,f(f(f(z,x),u),u))) = z.
f(f(x,f(f(z,y),f(z,x))),f(z,f(f(f(x,z),u),u))) = z.
f(f(x,f(f(z,x),f(z,y))),f(z,f(f(f(z,x),u),u))) = z.
f(f(x,f(f(z,x),f(z,y))),f(z,f(f(f(x,z),u),u))) = z.
f(f(x,f(f(z,x),f(y,z))),f(z,f(f(f(z,x),u),u))) = z.
f(f(x,f(f(z,x),f(y,z))),f(z,f(f(f(x,z),u),u))) = z.
f(f(x,f(f(z,y),f(z,x))),f(z,f(f(u,f(z,x)),u))) = z.
f(f(x,f(f(z,y),f(z,x))),f(z,f(f(u,f(x,z)),u))) = z.
f(f(x,f(f(z,x),f(z,y))),f(z,f(f(u,f(z,x)),u))) = z.
f(f(x,f(f(z,x),f(z,y))),f(z,f(f(u,f(x,z)),u))) = z.
f(f(x,f(f(z,x),f(y,z))),f(z,f(f(u,f(z,x)),u))) = z.
f(f(x,f(f(z,x),f(y,z))),f(z,f(f(u,f(x,z)),u))) = z.
f(f(x,f(f(z,y),f(z,x))),f(z,f(u,f(f(z,x),u)))) = z.
f(f(x,f(f(z,y),f(z,x))),f(z,f(u,f(f(x,z),u)))) = z.
f(f(x,f(f(z,x),f(z,y))),f(z,f(u,f(f(z,x),u)))) = z.
f(f(x,f(f(z,x),f(z,y))),f(z,f(u,f(f(x,z),u)))) = z.
f(f(x,f(f(z,x),f(y,z))),f(z,f(u,f(f(z,x),u)))) = z.
f(f(x,f(f(z,x),f(y,z))),f(z,f(u,f(f(x,z),u)))) = z.
f(f(x,f(f(z,y),f(z,x))),f(z,f(u,f(u,f(z,x))))) = z.
f(f(x,f(f(z,x),f(z,y))),f(z,f(u,f(u,f(z,x))))) = z.
f(f(x,f(f(z,x),f(y,z))),f(z,f(u,f(u,f(z,x))))) = z.
f(f(f(x,f(z,z)),z),f(f(f(f(y,u),u),f(y,z)),y)) = z.
f(f(f(x,f(z,z)),z),f(f(f(f(y,u),y),f(u,z)),u)) = z.
f(f(f(x,f(z,z)),z),f(f(f(y,f(u,y)),f(u,z)),u)) = z.
f(f(f(x,f(z,z)),z),f(f(f(y,f(y,u)),f(u,z)),u)) = z.
f(f(f(x,f(z,z)),z),f(f(f(y,z),f(f(u,y),u)),y)) = z.
f(f(f(x,f(z,z)),z),f(f(f(y,z),f(f(y,u),u)),y)) = z.
f(f(f(x,f(z,z)),z),f(f(f(y,z),f(u,f(u,y))),y)) = z.
f(f(f(x,f(z,z)),z),f(f(f(y,z),f(u,f(y,u))),y)) = z.
f(f(f(x,f(z,z)),z),f(y,f(f(f(u,y),u),f(z,y)))) = z.
f(f(f(x,f(z,z)),z),f(y,f(f(f(y,u),u),f(z,y)))) = z.
f(f(f(x,f(z,z)),z),f(y,f(f(u,f(u,y)),f(z,y)))) = z.
f(f(f(x,f(z,z)),z),f(y,f(f(u,f(y,u)),f(z,y)))) = z.
f(f(f(x,f(z,z)),z),f(y,f(f(z,y),f(f(u,y),u)))) = z.
f(f(f(x,f(z,z)),z),f(y,f(f(z,y),f(f(y,u),u)))) = z.
f(f(f(x,f(z,z)),z),f(y,f(f(y,z),f(f(u,y),u)))) = z.
f(f(f(x,f(z,z)),z),f(y,f(f(y,z),f(f(y,u),u)))) = z.
f(f(f(x,f(z,z)),z),f(y,f(f(z,y),f(u,f(u,y))))) = z.
f(f(f(x,f(z,z)),z),f(y,f(f(z,y),f(u,f(y,u))))) = z.
f(f(f(x,f(z,z)),z),f(y,f(f(y,z),f(u,f(u,y))))) = z.
f(f(f(x,f(z,z)),z),f(y,f(f(y,z),f(u,f(y,u))))) = z.
f(f(f(x,z),z),f(f(f(f(f(x,x),y),z),f(u,z)),x)) = z.
f(f(f(x,z),z),f(f(f(f(y,f(x,x)),z),f(u,z)),x)) = z.
f(f(f(x,z),z),f(f(f(z,y),f(f(f(x,x),u),z)),x)) = z.
f(f(f(x,z),z),f(f(f(y,z),f(f(f(x,x),u),z)),x)) = z.
f(f(f(x,z),z),f(f(f(z,y),f(f(u,f(x,x)),z)),x)) = z.
f(f(f(x,z),z),f(f(f(y,z),f(f(u,f(x,x)),z)),x)) = z.
f(f(f(x,z),z),f(f(f(z,y),f(x,z)),f(f(x,x),u))) = z.
f(f(f(x,z),z),f(f(f(y,z),f(x,z)),f(f(x,x),u))) = z.
f(f(f(x,z),z),f(f(f(x,z),f(y,z)),f(f(x,x),u))) = z.
f(f(f(x,z),z),f(f(f(z,y),f(x,z)),f(f(z,z),u))) = z.
f(f(f(x,z),z),f(f(f(y,z),f(x,z)),f(f(z,z),u))) = z.
f(f(f(x,z),z),f(f(f(x,z),f(y,z)),f(f(z,z),u))) = z.
f(f(f(x,z),z),f(f(f(z,y),f(x,z)),f(u,f(x,x)))) = z.
f(f(f(x,z),z),f(f(f(y,z),f(x,z)),f(u,f(x,x)))) = z.
f(f(f(x,z),z),f(f(f(x,z),f(y,z)),f(u,f(x,x)))) = z.
f(f(f(x,z),z),f(f(f(x,x),y),f(f(u,z),f(z,x)))) = z.
f(f(f(x,z),z),f(f(f(x,x),y),f(f(z,u),f(z,x)))) = z.
f(f(f(x,z),z),f(f(f(x,x),y),f(f(z,x),f(z,u)))) = z.
f(f(f(x,z),z),f(f(f(x,x),y),f(f(x,z),f(z,u)))) = z.
f(f(f(x,z),z),f(f(f(z,z),y),f(f(u,z),f(z,x)))) = z.
f(f(f(x,z),z),f(f(f(z,z),y),f(f(x,z),f(z,u)))) = z.
f(f(f(x,z),z),f(f(y,f(x,x)),f(f(u,z),f(z,x)))) = z.
f(f(f(x,z),z),f(f(y,f(x,x)),f(f(z,u),f(z,x)))) = z.
f(f(f(x,z),z),f(f(y,f(x,x)),f(f(z,x),f(z,u)))) = z.
f(f(f(x,z),z),f(f(y,f(x,x)),f(f(x,z),f(z,u)))) = z.
f(f(f(x,z),z),f(x,f(f(f(f(x,x),y),z),f(z,u)))) = z.
f(f(f(x,z),z),f(x,f(f(f(y,f(x,x)),z),f(z,u)))) = z.
f(f(f(x,z),z),f(x,f(f(z,f(f(x,x),y)),f(z,u)))) = z.
f(f(f(x,z),z),f(x,f(f(z,f(y,f(x,x))),f(z,u)))) = z.
f(f(f(x,z),z),f(x,f(f(z,y),f(z,f(f(x,x),u))))) = z.
f(f(f(x,z),z),f(x,f(f(y,z),f(z,f(f(x,x),u))))) = z.
f(f(f(x,z),z),f(x,f(f(z,y),f(z,f(u,f(x,x)))))) = z.
f(f(f(x,z),z),f(x,f(f(y,z),f(z,f(u,f(x,x)))))) = z.
f(f(x,z),f(f(f(f(z,x),z),f(y,z)),f(f(z,z),u))) = z.
f(f(x,z),f(f(f(f(x,z),z),f(y,z)),f(f(z,z),u))) = z.
f(f(x,z),f(f(f(z,f(z,x)),f(y,z)),f(f(z,z),u))) = z.
f(f(x,z),f(f(f(z,f(x,z)),f(y,z)),f(f(z,z),u))) = z.
f(f(x,z),f(f(f(z,z),y),f(f(f(z,x),z),f(z,u)))) = z.
f(f(x,z),f(f(f(z,z),y),f(f(f(x,z),z),f(z,u)))) = z.
f(f(x,z),f(f(f(z,z),y),f(f(z,f(z,x)),f(z,u)))) = z.
f(f(x,z),f(f(f(z,z),y),f(f(z,f(x,z)),f(z,u)))) = z.
f(f(x,z),f(f(f(z,z),y),f(f(z,u),f(z,f(z,x))))) = z.