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On the order of the unitary subgroup of modular group algebra

Victor Bovdi·A. L. Rosa
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Abstract

Let KG be a group algebra of a finite p-group G over a finite field K of characteristic p. We compute the order of the unitary subgroup of the group of units when G is either an extraspecial 2-group or the central product of such a group with a cyclic group of order 4 or G has an abelian subgroup A of index 2 and an element b such that b inverts each element of A.

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Victor Bovdi, A. L. Rosa. 2000-09-04. On the order of the unitary subgroup of modular group algebra. https://arxiv.org/abs/math/0009033

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