GCM 2010 The Third International Workshop on Graph Computation Models
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چکیده
We describe a concrete construction of all pushout complements for two given morphisms f : A → B, m : B → D in the category of hypergraphs, valid also for the case where f, m are non-injective. To our knowledge such a construction has not been discussed before in the literature. It is based on the generation of suitable equivalence relations. We also give a combinatorial interpretation and show how well-known coefficients from combinatorics, such as the Bell numbers, can be recovered.
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تاریخ انتشار 2010