Abstract | We investigate the problem of induction in the natural deduction construction of propositional linear-time temporal logic. The well known induction with the “always in the future” operator has been an obstacle in our previous developments of the proof search. Here we modify the formulation of the calculus by introducing new rules to deal with the “until” operator, show the correctness of a modified system and define proof search strategies for new rules based upon fixpoint characterisation of the Until operator. |
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