Orbits in unimodular Hermitian lattices

James, Donald G.

doi:10.1090/S0002-9947-1992-1089419-6

Orbits in unimodular Hermitian lattices
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Trans. Amer. Math. Soc. 332 (1992), 849-860 Request permission

Abstract:

Let $L$ be a unimodular indefinite hermitian lattice over the integers $\mathfrak {o}$ of an algebraic number field, and $N(L,c)$ the number of primitive representations of $c \in \mathfrak {o}$ by $L$ that are inequalivant modulo the action of the integral special unitary group $SU(L)$ on $L$. The value of $N(L,c)$ is determined from the local representations via a product formula.

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