Knuth paper-stack notation

Knuth paper-stack notation is an idea mentioned by Randall Munroe, creator of webcomic Xkcd, Comic 1162 (2013).
==Definition==
#Write the number on a stack of paper. If the stack doesn't fit in the room, move to step 2:
#Write the number of pages required to write the number from the previously executed step on a stack of paper. If the stack doesn't fit, repeat step 2 until it fits.
#When the stack finally fits, write the total number of iterations of step 2 on a card, and pin the card to the stack.
Assuming the card can fit 500 or so digits, this method can approximate numbers up to about \(10\uparrow\uparrow(10^{500})\) using Arrow notation.
==Sources==
Category:Notations
Category:Humor