CatDat

proset of integers w.r.t. divisibility

  • notation: (Z,)(\mathbb{Z},\mid)
  • objects: integers
  • morphisms: a unique morphism (a,b):ab(a,b) : a \to b if aa divides bb
  • Related categories: (N,)(\mathbb{N},\leq)

This is a proset, not a poset, because aa and a-a divide each other, but are not equal for a0a \neq 0. Notice that this category is equivalent (but not isomorphic) to (N,)(\mathbb{N},\mid).

Satisfied Properties

Properties from the database

Deduced properties

Unsatisfied Properties

Properties from the database

Deduced properties*

*This also uses the deduced satisfied properties.

Unknown properties

Special objects

  • terminal object: 00
  • initial object: 11
  • products: greatest common divisor
  • coproducts: the least common multiple, can be 00 for infinite families

Special morphisms

  • isomorphisms: the identities (a,a):aa(a,a) : a \to a and the isomorphisms (a,a):aa(a,-a) : a \to -a for aZa \in \mathbb{Z}
  • monomorphisms: every morphism
  • epimorphisms: every morphism
  • regular monomorphisms: same as isomorphisms
  • regular epimorphisms: same as isomorphisms