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arXiv · 0902.1312

On the minimal norm of a non-regular generalized character of an arbitrary finite group

Geoffrey R. Robinson
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Abstract

We prove that for any finite group G, the sum across non-identity elements of the squared absolute value of any generalized character of G which does not vanish on all non-identity elements of G is at least |G|/d -1, where d is the maximal degree of a complex irreducible character of G, and we identify all cases where this minimum possible value is attained.

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BibTeXRIS

Geoffrey R. Robinson. 2009-02-17. On the minimal norm of a non-regular generalized character of an arbitrary finite group. https://doi.org/10.1112/blms%2Fbdp129

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