I was mistaken above in the first identity, it is eml(1,eml(x,1)) = e - x Which then if you iterate gives x (ie is inverse of itself). eml(1,eml(eml(1,eml(x,

I was mistaken above in the first identity, it is eml(1,eml(x,1)) = e - x Which then if you iterate gives x (ie is inverse of itself). eml(1,eml(eml(1,eml(x,1)),1)) = x