Binary relation — бинарное отношение.
is a binary relation on if . is reflexive on if for all and irreflexive otherwise. is transitive on , if for all and implies . is symmetric, if implies , and antisymmetric on , if for all and implies .
The inverse of a relation , denoted by , is obtained by reversing each of the pairs belonging to , so that iff . Let denote the union and the intersection of a collection of relations in , where is some nonempty index set. Then iff for some in , and iff for each in .
- Евстигнеев В.А., Касьянов В.Н. Словарь по графам в информатике. — Новосибирск: Сибирское Научное Издательство, 2009.