Decomposition spaces, incidence algebras and Möbius inversion

Preprin

Coherent bicartesian and sesquicartesian categories

Sesquicartesian categories are categories with nonempty finite products and arbitrary finite sums, including the empty sum. Coherence is here demonstrated for sesquicartesian categories in which the first and the second projection from the product of the initial objec

Coherent bicartesian and sesquicartesian categories

Coherence is here demonstrated for sesquicartesian categories, which are categories with nonempty finite products and arbitrary finite sums, including the empty sum, where moreover the first and the second projection from the product of the initial object with itself are the same. (Ever