User blog comment:Chronolegends/X Hierarchy/@comment-80.98.179.160-20171026105341

I already defined an Extremely Fast Growing Hierarchy (EFGH). A(a,b,c)=c\uparrow^b a

It's defined as:

$$a_0(n)=n+1, a_{n+1}(n)=a_n^{n^n}(n^n), a_\varomega(n)=n\rightarrow n\rightarrow n\cdots_{\underbrace_n}\rightarrow n, a_{\varepsilon_0}(n)=n\rightarrow n\rightarrow n\cdots_{\underbrace_{n\rightarrow n\rightarrow\ n\cdots_{\underbrace_n}\rightarrow n}, a_{\Gamma_0}(n)=\rightarrow n\rightarrow n\cdots_{\underbrace_{n\rightarrow n\rightarrow n\cdots_{\underbrace_{\cdots_{\underbrace_{\rightarrow n\rightarrow n\cdots_{\underbrace_n}}\rightarrow n}}}}}}}\rbrace{n^n} $$