Dualities for Constraint Satisfaction Problems
Complexity of Constraints
Maltsev digraphs have a majority polymorphism
European Journal of Combinatorics
CSR'11 Proceedings of the 6th international conference on Computer science: theory and applications
| Hi-index | 0.00 |
Let B be a finite, core relational structureand let A be the algebra associated to B, i.e.whose terms are the operations on the universeof B that preserve the relations of B. Weshow that if A generates a so-called arithmetical variety then CSP(B), the constraint satisfaction problem associated to B, is solvable inLogspace; in fact CSP(B) is expressible insymmetric Datalog. In particular, we obtainthat if CSP(B) is expressible in Datalog andthe relations of B are invariant under a Maltsevoperation then CSP(B) is in symmetric Datalog.