On Corecursive Algebras for Functors Preserving Coproducts
نویسندگان
چکیده
For an endofunctor H on a hyper-extensive category preserving countable coproducts we describe the free corecursive algebra on Y as the coproduct of the final coalgebra for H and the free Halgebra on Y . As a consequence, we derive that H is a cia functor, i.e., its corecursive algebras are precisely the cias (completely iterative algebras). Also all functors H(−) + Y are then cia functors. For finitary set functors we prove that, conversely, if H is a cia functor, then it has the form H = W × (−) + Y for some sets W and Y . Digital Object Identifier 10.4230/LIPIcs...
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