Structure

sifted

A category C\C is sifted if it is inhabited and the diagonal functor Δ:C→C×C\Delta : \C \to \C \times \C is final, i.e. if it is non-empty and for any two objects X,Y∈CX,Y \in \C the category of cospans X→Z←YX \rightarrow Z \leftarrow Y is connected. A small category C\C is sifted if and only if colim⁡:SetC→Set\colim : \Set^{\C} \to \Set preserves finite products. This property is a weaker notion than being filtered.

Relevant implications

Examples

There are 115 categories with this property.

Counterexamples

There are 20 categories without this property.

Unknown

There are 0 categories for which the database has no information on whether they satisfy this property.

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