Mono-unary algebras are strongly dualizable
Jennifer Hyndman · Journal of the Australian Mathematical Society · 2002
Abstract We show that mono-unary algebras have rank at most two and are thus strongly dualizable. We provide an example of a strong duality for a mono-unary algebra using an alter ego with (partial) operations of arity at most two. This mono-unary algebra has rank two and generates the same quasivariety as an injective, hence rank one, mono-unary algebra.