CSP duality and trees of bounded pathwidth
Author
Carvalho, Catarina
Dalmau, Víctor
Krokhin, Andrei
Attention
2299/9618
Abstract
We study non-uniform constraint satisfaction problems definable in monadic Datalog stratified by the use of non-linearity. We show how such problems can be described in terms of homomorphism dualities involving trees of bounded pathwidth and in algebraic terms. For this, we introduce a new parameter for trees that closely approximates pathwidth and can be characterised via a hypergraph searching game.