CatDat

category of combinatorial species

  • notation: Sp\mathbf{Sp}
  • objects: combinatorial species, defined as functors BFinSet\mathbb{B} \to \mathbf{FinSet}, where B\mathbb{B} is the category of finite sets and bijections
  • morphisms: natural transformations
  • Related categories: FinSet\mathbf{FinSet}B\mathbb{B}
  • nLab Link

Most categorical properties are immediately inferred from FinSet\mathbf{FinSet}. Notice that this category is not locally small; it is just equivalent to a locally small category.

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

There are 6 properties for which the database doesn't have an answer if they are satisfied or not. Please help to contribute the data!

Special objects

  • terminal object: species XX with Xn=1X_n = 1
  • initial object: species XX with Xn=X_n = \emptyset
  • products: [finite case] pointwise defined direct product
  • coproducts: [finite case] pointwise finite disjoint union

Special morphisms

  • isomorphisms: natural isomorphisms
  • monomorphisms: pointwise injective natural transformations
  • epimorphisms: pointwise surjective natural transformations
  • regular monomorphisms: same as monomorphisms
  • regular epimorphisms: same as epimorphisms