ThmDex – An index of mathematical definitions, results, and conjectures.
▼ Set of symbols
▼ Alphabet
▼ Deduction system
▼ Theory
▼ Zermelo-Fraenkel set theory
▼ Set
▼ Collection of sets
▼ Set union
▼ Successor set
▼ Inductive set
▼ Set of inductive sets
▼ Set of natural numbers
Definition D226
Set of initial natural numbers
Results
▶ Relationship with the sum of initial natural numbers and the binomial coefficient