A characterization of the $n$-ary many-sorted closure operators and a many-sorted Tarski irredundant basis theorem

Juan Climent Vidal, Enric Cosme Llópez

A theorem of single-sorted algebra states that, for a closure space $(A,J)$ and a natural number $n$, the closure operator $J$ on the set $A$ is $n$-ary if, and only if, there exis…