Universal Z-lattices of Minimal Rank
نویسندگان
چکیده
Let UZ(n) be the minimal rank of n-universal Z-lattices, by which we mean positive definite Z-lattices which represent all positive Z-lattices of rank n. It is a well known fact that UZ(n) = n + 3 for 1 ≤ n ≤ 5. In this paper, we determine UZ(n) and find all n-universal lattices of rank UZ(n) for 6 ≤ n ≤ 8.
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