{ "id": "1807.08238", "version": "v1", "published": "2018-07-22T06:02:03.000Z", "updated": "2018-07-22T06:02:03.000Z", "title": "Bounding the number of characters in a block of a finite group", "authors": [ "Benjamin Sambale" ], "comment": "16 pages", "categories": [ "math.RT" ], "abstract": "We present a strong upper bound on the number k(B) of irreducible characters of a p-block B of a finite group G in terms of local invariants. More precisely, the bound depends on a chosen major B-subsection (u,b), its normalizer N_G(\\langle u\\rangle,b) in the fusion system and a weighted sum of the Cartan invariants of b. In this way we strengthen and unify previous bounds given by Brauer, Wada, K\\\"ulshammer--Wada, H\\'ethelyi--K\\\"ulshammer--Sambale and the present author.", "revisions": [ { "version": "v1", "updated": "2018-07-22T06:02:03.000Z" } ], "analyses": { "keywords": [ "finite group", "strong upper bound", "chosen major b-subsection", "local invariants", "cartan invariants" ], "note": { "typesetting": "TeX", "pages": 16, "language": "en", "license": "arXiv", "status": "editable" } } }