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arXiv · 1302.1929

ZL-amenability constants of finite groups with two character degrees

Mahmood Alaghmandan·Yemon Choi·Ebrahim Samei
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Abstract

We calculate the exact amenability constant of the centre of $\ell^1(G)$ when $G$ is one of the following classes of finite group: dihedral; extraspecial; or Frobenius with abelian complement and kernel. This is done using a formula which applies to all finite groups with two character degrees. In passing, we answer in the negative a question raised in work of the third author with Azimifard and Spronk (J. Funct. Anal. 2009).

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Mahmood Alaghmandan, Yemon Choi, Ebrahim Samei. 2013-02-08. ZL-amenability constants of finite groups with two character degrees. https://doi.org/10.4153/cmb-2013-022-1

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