MBN

MBN, or Miner's Bracket Enumeration, was inspired by BEAF and weaker than it, but can produce big numbers.

Formula:

If you take [4, 3, 9], you do:

$$4\underbrace{\uparrow\cdots\uparrow}_{3\underbrace{\uparrow\cdots\uparrow}_{9}3}4$$ . And if you take [8, 3, 77, 14, 19], than it will be

$$8\underbrace{\uparrow\cdots\uparrow}_{3\underbrace{\uparrow\cdots\uparrow}_{77\underbrace{\uparrow\cdots\uparrow}_{14\underbrace{\uparrow\cdots\uparrow}_{19}14}77}3}8$$ . But you can't create big numbers easily, as Graham's Number would be

$$[\underbrace{3, 3 \cdots 3, 3}_{\text{64 3's}}, 4]$$ .

And if you understand the pattern, you understood the function!