2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/100203Kuratowski's 14-set theorem says that in a topological space, 14 is the maximum possible number of distinct sets which can be generated from a fixed set by taking closures and complements. In this article we consider the analogous questions for any possible subcollection of the operations {closure, complement, interior, intersection, union}, and any number of initially given sets. We use the algebraic "topological calculus" to full advantage.11 pagesGeneral TopologyMathematical Physics54A05; 06F05text