Mathematical Menagerie

Moser's number is a truly gigantic mathematical constant that provides an absurdly large upper bound for a hypercube-path Ramsey problem.

To give a sense of how big a math bear Moser is, if you start with a 2, and raise it to the power of 2, and then raise 2 to the power of that, and raise 2 to the power of that, you get 2^65536 which has many orders of magnitude more digits than the total number of atoms in the universe. If you stack 65,536 2s in such a "power tower," that's called Mega. Then, Moser's number is defined as a tower of 2s of height Mega–which is vastly beyond anything describable with normal notation, so people use a shorthand involving polygons.