Steinitz classes of unimodular lattices
نویسنده
چکیده
For each prime l with l ≡ 7 (mod 8), we define an action of the ring O = Z[ 2(1 + √ −l)] on the unimodular lattice D l+1 using a Paley matrix. We determine the isomorphism class of D l+1 as an O-module. In particular we show that unless l = 7, D l+1 is not a free O-module. We note a consequence for the Leech lattice.
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ورودعنوان ژورنال:
- Eur. J. Comb.
دوره 25 شماره
صفحات -
تاریخ انتشار 2004