Exotetrommthet

Exotetrommthet is equal to \(f_{\theta(\Omega \uparrow\uparrow 10^{18})}(10)\) using the fast-growing hierarchy. The term was coined by wiki user Denis Maksudov.

It is equal to \(f_{\psi(\Omega \uparrow\uparrow (10^{18}+1))}(10)\) using Buchholz's psi-function.