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arXiv · 0901.0970

Midwest cousins of Barnes-Wall lattices

Robert L. Griess Jr
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Abstract

Given a rational lattice and suitable set of linear transformations, we construct a cousin lattice. Sufficient conditions are given for integrality, evenness and unimodularity. When the input is a Barnes-Wall lattice, we get multi-parameter series of cousins. There is a subseries consisting of unimodular lattices which have ranks $2^{d-1}\pm 2^{d-k-1}$, for odd integers $d\ge 3$ and integers $k=1,2, ..., \frac {d-1}2$. Their minimum norms are moderately high: $2^{\lfloor \frac d2 \rfloor -1}$.

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Robert L. Griess Jr. 2009-10-11. Midwest cousins of Barnes-Wall lattices. https://arxiv.org/abs/0901.0970

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