Triangle read by rows, T(n,k) = 2*binomial(n,k) if k>0, (0<=k<=n), left column = (1,2,2,2,...).
1, 2, 2, 2, 4, 2, 2, 6, 6, 2, 2, 8, 12, 8, 2, 2, 10, 20, 20, 10, 2, 2, 12, 30, 40, 30, 12, 2, 2
1 seqfan posts
Wed Jul 8 14:39:22 CEST 2009 [seqfan] bulk of A046055 (Orders of finite Abelian groups)