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arXiv · 1802.04571

$CI$-property for decomposable Schur rings over an abelian group

István Kovács·Grigory Ryabov
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Abstract

A Schur ring over a finite group is said to be decomposable if it is the generalized wreath product of Schur rings over smaller groups. In this paper we establish a sufficient condition for a decomposable Schur ring over the direct product of elementary abelian groups to be a $CI$-Schur ring. By using this condition we reprove in a short way known results on the $CI$-property for decomposable Schur rings over an elementary abelian group of rank at most $5$.

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István Kovács, Grigory Ryabov. 2018-10-23. $CI$-property for decomposable Schur rings over an abelian group. https://arxiv.org/abs/1802.04571

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