Ordinal Number

Author

Eric W. Weisstein
June 11, 2003

This notebook downloaded from http://mathworld.wolfram.com/notebooks/Logic/OrdinalNumber.nb.

For more information, see Eric's MathWorld entry http://mathworld.wolfram.com/OrdinalNumber.html.

©2005 Wolfram Research, Inc. except for portions noted otherwise

Additional Authors

ord[] by Matthew Szudzik
June 11, 2003

Enumeration

ord[n_]:=Nest[Union[#,{#}]&,{},n]

Table[{n,ord[n]},{n,3}]//ColumnForm

ord[n_]:=Nest[#⋃{#}&,{},n]