In mathematics, Moser's polygon notation is a means of expressing certain large numbers. It is the obvious extension of Steinhaus polygon notation, ie., n written in an (m+1)-gon means "n in n m-gons".
means nn
means "n in n triangles"
means "n in n squares"
etc.
Moser's number is "2 in a Megagon", using Steinhaus' Mega.
In more formal notation, let