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
▼	Binary endorelation

Definition D2696

Digraph

Formulation 0

An D548: Ordered pair $G = (X, \mathcal{E})$ is a digraph if and only if

(1)	$X$ is a D11: Set
(2)	\begin{equation} \mathcal{E} \subseteq X \times X \end{equation}

Formulation 1

An D548: Ordered pair $G = (X, \mathcal{E})$ is a digraph if and only if

(1)	$X$ is a D11: Set
(2)	$\mathcal{E}$ is a D78: Subset of $X \times X$

Children