On OBDDs for CNFs of bounded treewidth

Igor Razgon

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arXiv · 1308.3829

On OBDDs for CNFs of bounded treewidth

Igor Razgon

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Abstract

In this paper we show that a CNF cannot be compiled into an Ordered Binary Decision Diagram (OBDD) of fixed-parameter size parameterized by the primal graph treewidth of the CNF. Thus we provide a parameterized separation between OBDDs and Sentential Decision Diagrams (SDDs) for which such fixed-parameter compilation is possible. In fact, we demonstrate that the proposed lower bound also yields a classical (non-parameterized) separation of OBDDs and SDDs. We also show that the best existing parameterized upper bound for OBDDs in fact holds for incidence graph treewidth parameterization.

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Igor Razgon. 2013-08-18. On OBDDs for CNFs of bounded treewidth. https://arxiv.org/abs/1308.3829

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