User blog comment:Alejandro Magno/Ideas for ExE/@comment-11227630-20141001154728

The #'s can take on multiplication, exponentiation, tetration, expansion and so on. More generally we have Ea f1(#) b, where f1(n) is some recursive googological function: n*n, n^n, E(n)n##n or something like that.

Now imagine f1(n) = En f2(#) n, where f2(n) is some recursive googological function.

Now imagine f2(n) = En f3(#) n, where f3(n) is some recursive googological function.

I believe this reach $$\psi(\Omega_\omega)$$, but more details are needed.