ar X iv : m at h / 04 05 40 1 v 1 [ m at h . G N ] 2 1 M ay 2 00 4 VARIATIONS ON KURATOWSKI ’ S 14 - SET THEOREM
نویسنده
چکیده
Kuratowski’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.
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