User blog comment:JTOnstead20/T Notation/@comment-27516045-20161107211506

I have extension

n(t^t)x = n(t^x)n

n(t^t*t)x = makes towers of (t^t)

n(t^t*t^t)x = n(t^t*t^x)n

n(t^t^2)x = n(t^t*t^t*...)n (x t's)

n(t^t^t)x = n(t^t^x)n

...

And that's e_0