Sagan

The term sagan, named after , is defined as four billion = 4,000,000,000.http://www.neatorama.com/2009/11/09/10-neat-facts-about-carl-sagan
It was also the prize for correctly answering the first eight questions in the Turkish game show in first .
== Approximations ==
Notation 	Lower bound 	Upper bound
Scientific notation 	\(4\times10^9\) 	\(4\times10^9\)
Arrow notation 	\(83\uparrow5\) 	\(40\uparrow6\)
Steinhaus-Moser Notation 	9[3] 	10[3]
Copy notation 	3[10] 	4[10]
Taro's multivariable Ackermann function	A(3,28) 	A(3,29)
Pound-Star Notation 	#*(6)*11 	#*(1,0,5)*3
BEAF 	{83,5} 	{40,6}
Hyper-E notation 	4E9 	4E9
Bashicu matrix system 	(0)[63245] 	(0)[63246]
Hyperfactorial array notation 	12! 	13!
Fast-growing hierarchy 	\(f_2(27)\) 	\(f_2(28)\)
Hardy hierarchy 	\(H_{\omega^2}(27)\) 	\(H_{\omega^2}(28)\)
Slow-growing hierarchy 	\(g_{\omega^9\times4}(10)\)	\(g_{\omega^9\times4}(10)\)
== Sources ==
Category:Numbers
Category:Achilles numbers
Category:Class 2
Category:Eponymous numbers
Category:Game show prizes
Category:Numbers with 7 to 29 digits