Heptakisillion

Heptakisillion is equal to \(10^{3\times 10^{3\times 10^{3\times 10^{3\times 10^{3\times 10^{21} } } } } +3}\). The term was coined by Nirvana Supermind and its part of his unofficial extension of Bower's -illion system which ended at multillion.
==Etymology==
This name comes from Greek Quantitative Prefix "heptakis" and the suffix "-illion".
==Approximations==
Notation 	Expression
Up-arrow notation 	\(10\uparrow(3\times10\uparrow(3\times10\uparrow(3\times10\uparrow(3\times10\uparrow(3\times10\uparrow21))))))+3)\)
Chained arrow notation	\(10\rightarrow(3\times10\rightarrow(3\times10\rightarrow(3\times10\rightarrow(3\times10\rightarrow(3\times10\rightarrow21))))))+3)\)
BEAF 	\(\{10,3\times\{10,3\times\{10,3\times\{10,3\times\{10,3\times\{10,21\}\}\}\}\}+3\}\)
==Sources==
Category:Numbers and functions by CompactStar