Certain self-dual codes over ℤ4 and the odd Leech lattice
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Recently, alternative constructions of the Leech lattice and the shorter Leech lattice have been discovered using self-dual codes over ℤ4. In this paper, we provide a classification of length 24 double circulant Type I codes over ℤ4 with minimum Euclidean weight 12. These codes determine (via Construction A4) the odd Leech lattice, which is a unique 24-dimensional odd unimodular lattice with minimum norm 3.
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