Pentation

Repeated tetration or hyper-4 is pentation or hyper-5. It can make HUGE numbers very, very quickly.

For example: $2[5]2 = 2[4]2 = 2^2 = 4$ If we increase the last $2$ of $2[5]2$, then let's see what happens: $2[5]3 = 2[4](2[4]2) = 2[4]4 = 2^{2^{2^{2}}} = 2^{16} = 65536$ Pentation grows much faster than what you're used to, like exponentiation.

We know that repeated addition is multiplication, repeated multiplication is exponentiation (a↑b), repeated exponentiation is tetration (a↑↑b), and what is repeated tetration, pentation (a↑↑↑b)!

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