von Neumann integer (mathematics) A finite von Neumann ordinal.
The von Neumann integer N is a finite set with N elements which are the von Neumann integers 0 to N-1. Thus 0 = {} = {} 1 = {0} = {{}} 2 = {0, 1} = {{}, {{}}} 3 = {0, 1, 2} = {{}, {{}}, {{}, {{}}}} ...
The set of von Neumann integers is infinite, even though each of its elements is finite. [Origin of name?] Last updated: 1995-03-30