CSP duality and trees of bounded pathwidth
نویسندگان
چکیده
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.
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ورودعنوان ژورنال:
- Theor. Comput. Sci.
دوره 411 شماره
صفحات -
تاریخ انتشار 2010