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arXiv · 0904.2521

Universal Structures and the logic of Forbidden Patterns

Florent R. Madelaine
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Abstract

Forbidden Patterns Problems (FPPs) are a proper generalisation of Constraint Satisfaction Problems (CSPs). However, we show that when the input is connected and belongs to a class which has low tree-depth decomposition (e.g. structure of bounded degree, proper minor closed class and more generally class of bounded expansion) any FPP becomes a CSP. This result can also be rephrased in terms of expressiveness of the logic MMSNP, introduced by Feder and Vardi in relation with CSPs. Our proof generalises that of a recent paper by Nesetril and Ossona de Mendez. Note that our result holds in the general setting of problems over arbitrary relational structures (not just for graphs).

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Florent R. Madelaine. 2009-04-16. Universal Structures and the logic of Forbidden Patterns. https://doi.org/10.2168/lmcs-5(2%3A13)2009

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