All possible 36 distinct level-2 eml functions of one variable (the first 18 of them with entirely Real outputs, the other 18 with "intermediate" complex-valued components):

https://imgur.com/a/K7AoOFi

It would be fun to catalogue all one-variable functions that can be represented as binary trees of fixed depth in this way and then encode the trees in binary. Lots of these functions in old math book tables would look very different with a plain hash lookup and the identities in such books would prove themselves.