Free Groups and Subgroups of Finite Index in the Unit Group of an Integral Group Ring∗
نویسندگان
چکیده
In this article we construct free groups and subgroups of finite index in the unit group of the integral group ring of a finite non-abelian group G for which every non-linear irreducible complex representation is of degree 2 and with commutator subgroup G′ a central elementary abelian 2-group.
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