Decidability of the Monadic Shallow Linear First-Order Fragment with Straight Dismatching Constraints

Andreas Teucke; Christoph Weidenbach

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arXiv · 1703.02837

Decidability of the Monadic Shallow Linear First-Order Fragment with Straight Dismatching Constraints

Andreas Teucke·Christoph Weidenbach

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Abstract

The monadic shallow linear Horn fragment is well-known to be decidable and has many application, e.g., in security protocol analysis, tree automata, or abstraction refinement. It was a long standing open problem how to extend the fragment to the non-Horn case, preserving decidability, that would, e.g., enable to express non-determinism in protocols. We prove decidability of the non-Horn monadic shallow linear fragment via ordered resolution further extended with dismatching constraints and discuss some applications of the new decidable fragment.

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Andreas Teucke, Christoph Weidenbach. 2017-05-24. Decidability of the Monadic Shallow Linear First-Order Fragment with Straight Dismatching Constraints. https://arxiv.org/abs/1703.02837

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