Let $\mathbb{N}$ be the D225: Set of natural numbers.
A D11: Set $X$ is a finite set if and only if
\begin{equation}
\exists \, N \in \mathbb{N} :
\text{Bij}(\{ 1, \ldots, N \} \to X)
\neq \emptyset
\end{equation}
| ▼ | Set of symbols |
| ▼ | Alphabet |
| ▼ | Deduction system |
| ▼ | Theory |
| ▼ | Zermelo-Fraenkel set theory |
| ▼ | Set |
| ▼ | Binary cartesian set product |
| ▼ | Binary relation |
| ▼ | Map |
| ▼ | Bijective map |
| ▼ | Set of bijections |
| ▼ | Countable set |
| ▶ | D1880: Cofinite set |
| ▶ | R4292: Finite cartesian product of finite sets is finite |