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%I #8 Mar 30 2012 16:50:19
%S 1,3,135,16335,75700575
%N Number of vectors in Barnes-Wall lattice BW_{2^n} with twice the minimal norm, divided by 2^(n+1).
%C Converges 2-adically.
%H N. Heninger, E. M. Rains and N. J. A. Sloane, <a href="http://arXiv.org/abs/math.NT/0509316">On the Integrality of n-th Roots of Generating Functions</a>, J. Combinatorial Theory, Series A, 113 (2006), 1732-1745.
%H <a href="/index/Ba#BW">Index entries for sequences related to Barnes-Wall lattices</a>
%K hard,nonn
%O 1,2
%A Eric Rains (rains(AT)caltech.edu) and _N. J. A. Sloane_, Sep 27 2005