User blog comment:PsiCubed2/Defining Letter Notation up to N without Arrays/@comment-25337554-20180419103334/@comment-30754445-20180419105212

You could see it that way. But then again, can you name a googological notation that isn't some sort of "a way to write arrays"? Also, arrays are just another way of encoding ordinals. Pretty much every single recursive notation is just a variation of the good old FGH in disguise.

At any rate, the point here was simply to have letter equivalents for the "intermediate" functions. So instead of expanding (say) N2.04 like this:

N2.04 ≈ M2(1,6)&#124;2(1,5)&#124;7(1,3)&#124;LK3J126&#124;25&#124;F6E84085174

We could write it all in the same kind of notation:

N2.04 ≈ M2(Lh)2(Lg)7LeLK3J12(Hf)2HeF6E84085174