Icosa-exaxis

Icosa-exaxis is equal to \(10\uparrow\uparrow\uparrow\uparrow\uparrow20\) or 10 heptated to 20. This term was coined by YouTuber Douglas Shamlin Jr.D. Shamlin Jr., Ultimate List of Large Numbers - Part 1 of 4 | The Beginning! (Reuploaded by Dr2xmillion). Accessed 2022-05-30.
==Approximations==
Notation 	Approximation
Hyper-E Notation 	\(E1\#1\#1\#1\#20\) (exact)
Bird's array notation 	\(\{10,20,5\}\) (exact)
Fast-growing hierarchy	\(f_6(20)\)
==Sources==
Category:Numbers
Category:Up-arrow notation level
Category:Videos