Number of n-dimensional determinant 2 lattices.

Terms

a(0) =0a(1) =1a(2) =1a(3) =1a(4) =1a(5) =1a(6) =1a(7) =2a(8) =2a(9) =3a(10) =3a(11) =4a(12) =4a(13) =6a(14) =7a(15) =11a(16) =14a(17) =24a(18) =30