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arXiv · 1905.06143

A Non-wellfounded, Labelled Proof System for Propositional Dynamic Logic

Simon Docherty·Reuben N. S. Rowe
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Abstract

We define a infinitary labelled sequent calculus for PDL, G3PDL^{\infty}. A finitarily representable cyclic system, G3PDL^{\omega}, is then given. We show that both are sound and complete with respect to standard models of PDL and, further, that G3PDL^{\infty} is cut-free complete. We additionally investigate proof-search strategies in the cyclic system for the fragment of PDL without tests.

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Simon Docherty, Reuben N. S. Rowe. 2019-05-15. A Non-wellfounded, Labelled Proof System for Propositional Dynamic Logic. https://arxiv.org/abs/1905.06143

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