ThmDex – An index of mathematical definitions, results, and conjectures.
▼ Set of symbols
▼ Alphabet
▼ Deduction system
▼ Theory
▼ Zermelo-Fraenkel set theory
▼ Set
▼ Binary cartesian set product
▼ Binary relation
▼ Map
Definition D2901
Multiset
Formulation 0
An D548: Ordered pair $M = (X, f)$ is a multiset if and only if
(1) $X$ is a D11: Set
(2) \begin{equation} f : X \to \mathbb{N} \cup \{ \infty \} \end{equation}