%I A054907
%S A054907 1,0,0,0,0,0,0,0,1,0,0,0,1,0,1,1,3,1,4,3,12,12,28,49,180,368
%N A054907 Number of n-dimensional unimodular lattice (or quadratic forms) containing 
               no vectors of norm 1.
%D A054907 J. H. Conway and N. J. A. Sloane, "Sphere Packings, Lattices and Groups", 
               Springer-Verlag, p. 49.
%Y A054907 Cf. A005134, A054908-A054909, A054911.
%Y A054907 Sequence in context: A035626 A082587 A060043 this_sequence A089554 A129246 
               A125608
%Y A054907 Adjacent sequences: A054904 A054905 A054906 this_sequence A054908 A054909 
               A054910
%K A054907 nonn,nice,hard
%O A054907 0,17
%A A054907 N. J. A. Sloane (njas(AT)research.att.com), May 23 2000