Abstract:
The fragment of the polymodal provability logic $\mathbf{GLP}$ in the language with connectives $\top$, $\wedge$, and $\langle n\rangle$ for all $n\in\omega$ is considered. For this fragment, a deductive system it constructed, a Kripke semantics is proposed, and a polynomial bound for the complexity of a decision procedure is obtained.
Keywords:modal logic, graded provability logic $\mathbf{GLP}$, equational calculus, deductive system, Kripke semantics, complexity of a decision procedure.