Cut approach to invariance groups of lattice-valued functions

Abstract

This paper deals with lattice-valued n-variable functions on a k-element domain, considered as a generalization of lattice-valued Boolean functions. We investigate invariance groups of these functions, i.e., the group of such permutations that leaves the considered function invariant. We show that the invariance groups of lattice-valued functions depend only on the cuts of the function. Furthermore, we construct such lattice-valued Boolean function (and its generalization), the cuts of which represent all representable invariance groups.