On integral representations of twisted group rings

Abstract

Let ω be a primitive 2 n -root of unity, for n ⩾ 2, and Λ = Z[ ω] ∘ G be the twisted group ring, where G = 〈 σ: σ 2= 1〉 and where σ · α = \\ ̄ gaσ, α ϵ Z[ω] , with \\ ̄ ga the complex conjugate of α. The purpose of this paper is to find the non-isomorphic indecomposable Λ-lattices.