Number of series-reduced powerful rooted trees with n nodes.

Terms

a(0) =1a(1) =0a(2) =1a(3) =1a(4) =1a(5) =1a(6) =2a(7) =1a(8) =3a(9) =3a(10) =4a(11) =4a(12) =8a(13) =5a(14) =11a(15) =10a(16) =14a(17) =14a(18) =24a(19) =18a(20) =34a(21) =32a(22) =46a(23) =45a(24) =72a(25) =60a(26) =103a(27) =96a(28) =138a(29) =137