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
Total binary relation
Definition D360
Right-total binary relation
Formulation 0
A D4: Binary relation $B = (X \times Y, R)$ is a right-total binary relation if and only if \begin{equation} \forall \, y \in Y : \exists \, x \in X : (x, y) \in R \end{equation}