Fuga- is a prefix used on a number \(n\) to indicate \(((...((n^n)^n)^n ... ^n)\) with n amount of n's, or \(n\downarrow \downarrow n\) in down-arrow notation. It was invented by Allstair Cockburn to continue the idea of the gar- prefix invented by his son. The first few values of fuga-n are 1, 4, 19,683, and 3.4028*1038. It is an example of a function with growth rates slightly above double-exponential.
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