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