a(n) = [x^n] Product_{k>=2} (1 + x^k)^n.

Terms

a(0) =1a(1) =0a(2) =2a(3) =3a(4) =10a(5) =30a(6) =77a(7) =252a(8) =682a(9) =2145a(10) =6182a(11) =18887a(12) =56317a(13) =170534a(14) =515930a(15) =1563843a(16) =4759338a(17) =14480073a(18) =44203595a(19) =134972504a(20) =412984510a(21) =1264601502a(22) =3877302717a(23) =11898761051a(24) =36548512477a(25) =112358685555a(26) =345673541514