A Complete Classification of Complexity in Allens Algebra in the Presence of a Non-Trivial Basic Relation
نویسندگان
چکیده
We study fragments of Allen’s algebra that contain a basic relation distinct from the equality relation. We prove that such a fragment is either NPcomplete or else contained in some already known tractable subalgebra. We obtain this result by giving a new uniform description of known maximal tractable subalgebras and then systematically using an algebraic technique for description of maximal subalgebras with a given property. This approach avoids the need for extensive computerassisted search.
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