ThmDex – An index of mathematical definitions, results, and conjectures.
Set of symbols
Alphabet
Deduction system
Theory
Zermelo-Fraenkel set theory
Set
Transitive set
Ordinal number
Definition D686
Class of ordinal numbers
Formulation 0
The class of ordinal numbers is the D684: Class \begin{equation} \mathsf{Ord} : = \{ \alpha \mid \alpha \text{ is an ordinal number} \} \end{equation}
Children
Strict ordinal number ordering relation