Consider the problem of deciding whether a Boolean formula f is self-dual, i.e. f is logically equivalent to its dual formula f d , deened by f d (x) = f (x). This problem is a well-studied problem in several areas like theory of coteries, database theory, hypergraph theory or computational learning theory. In this paper we exhibit polynomial time algorithms for testing self-duality for several...

Many approaches to deciding the satisfiability of quantifier-free formulae with respect to a background theory T—also known as SatisfiabilityModulo Theory, or SMT(T)—rely on the integration between an enumerator of truth assignments and a decision procedure for conjunction of literals in T. When the background theory T is the combination T1 ∪ T2 of two simpler theories, the approach is typicall...

Submodular constraints play an important role both in theory and practice of valued constraint satisfaction problems (VCSPs). It has previously been shown, using results from the theory of combinatorial optimisation, that instances of VCSPs with submodular constraints can be minimised in polynomial time. However, the general algorithm is of order O(n) and hence rather impractical. In this paper...

03D15 (Mathematical logic and foundations / Recursion theory / Complexity of computation), 03E40 (Mathematical logic and foundations / Set theory / Other aspects of forcing and Boolean-valued models), 68Q15 (Computer science / Theory of computing / Complexity classes).

Wqo theory = well quasi ordering theory, is a branch of combinatorics which has proved to be a fertile source of deep metamathematical pheneomena. In wqo theory, one freely uses some overtly set theoretic arguments. They are definitely noticeable, although they come fairly early in the interpretation hierarchy. Way before, say, ZFC. A qo (quasi order) is a reflexive transitive relation (A,£). A...