We present algebraic conditions on constraint languages Γ that ensure the hardness of the constraint satisfaction problem CSP(Γ) for complexity classes L, NL, P, NP and ModpL. Th...
Abstract. We study the lattice structure of sets (monoids) of surjective hyper-operations on an n-element domain. Through a Galois connection, these monoids form the algebraic coun...
An instance of the maximum constraint satisfaction problem (Max CSP) is a nite collection of constraints on a set of variables, and the goal is to assign values to the variables ...
Peter Jonsson, Andrei A. Krokhin, Fredrik Kuivinen