Category:Enumerations

This category contains results about Enumerations.
Definitions specific to this category can be found in Definitions/Enumerations.

Finite Sets

Let $X$ be a finite set of cardinality $n \in \N$.

An enumeration of $X$ is a bijection $x: \N_n \to X$, where $\N_n = \set {1, \ldots, n}$.

Countably Infinite Sets

Let $X$ be a countably infinite set.

An enumeration of $X$ is a bijection $x: \N \to X$.