This reminded me of tetration and Knuth's up-arrow notation. It's basically repeated exponentiation. Searching now, I just learned of tetrofactorial, which is

This reminded me of tetration and Knuth's up-arrow notation. It's basically repeated exponentiation. Searching now, I just learned of tetrofactorial, which is a factorial using tetration operations. There's also pentation which is repeated tetration. And there's a whole wiki for it here: googology.fandom.com It's fun because the numbers are so big it's basically infinity but any of those numbers is still nothing compared to infinity.