The Subvariety of Q-heyting Algebras Generated by Chains
نویسنده
چکیده
The variety QH of Heyting algebras with a quantifier [14] corresponds to the algebraic study of the modal intuitionistic propositional calculus without the necessity operator. This paper is concerned with the subvariety C of QH generated by chains. We prove that this subvariety is characterized within QH by the equations ∇(x∧ y) ≈ ∇x∧∇y and (x → y)∨ (y → x) ≈ 1. We investigate free objects in C.
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