Modal operators on BCK-algebras

Document Type : Original Article


Department of Mathematics, University of Bojnord, Bojnord, Iran


In this paper, modal operators on BCK-algebras, especially BCK-algebras with condition (S) are introduced and several properties and characterizations of them are investigated. Also, it is investigated under what conditions these modal  operators form a lattice. Furthermore, some special modal operators are introduced and their properties and  characterizations of them are obtained, especially in some classes of BCK-algebras such as positive implicative BCK- algebras.


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