User:12AbBa/FGH array notation

I've finally decided to turn my blog posts into a user page. I found out how the notation could correspond exactly with  FGH, so I decided to turn A function into FGH array notation. It is still denoted by the letter A.

Basic
nA(0)=n+1,

nA(k+1)=nA(k)A(k)...A(k) with n As.

nA(k)=fk(n).