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arXiv · 1203.1347

Caterpillar dualities and regular languages

Péter L. Erdős·Claude Tardif·Gábor Tardos
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Abstract

We characterize obstruction sets in caterpillar dualities in terms of regular languages, and give a construction of the dual of a regular family of caterpillars. We show that these duals correspond to the constraint satisfaction problems definable by a monadic linear Datalog program with at most one EDB per rule.

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Péter L. Erdős, Claude Tardif, Gábor Tardos. 2012-03-06. Caterpillar dualities and regular languages. https://doi.org/10.1137/120879270

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