{ "id": "1002.0320", "version": "v2", "published": "2010-02-01T20:01:54.000Z", "updated": "2010-07-01T11:43:15.000Z", "title": "Finite generation of iterated wreath products", "authors": [ "Ievgen Bondarenko" ], "comment": "7 pages. An example of a branch group with maximal subgroups of infinite index is added", "categories": [ "math.GR" ], "abstract": "Let $(G_n,X_n)$ be a sequence of finite transitive permutation groups with uniformly bounded number of generators. We prove that the infinitely iterated permutational wreath product $...\\wr G_2\\wr G_1$ is topologically finitely generated if and only if the profinite abelian group $\\prod_{n\\geq 1} G_n/G'_n$ is topologically finitely generated. As a corollary, for a finite transitive group $G$ the minimal number of generators of the wreath power $G\\wr...\\wr G\\wr G$ ($n$ times) is bounded if $G$ is perfect, and grows linearly if $G$ is non-perfect. As a by-product we construct a finitely generated branch group, which has maximal subgroups of infinite index, answering [2,Question 14].", "revisions": [ { "version": "v2", "updated": "2010-07-01T11:43:15.000Z" } ], "analyses": { "subjects": [ "20F05", "20E22", "20E18", "20E08" ], "keywords": [ "iterated wreath products", "finite generation", "profinite abelian group", "finite transitive permutation groups" ], "note": { "typesetting": "TeX", "pages": 7, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2010arXiv1002.0320B" } } }