Number of simple unlabeled graphs on n nodes with exactly 3 connected components that are trees or cycles.

A215983

Number of simple unlabeled graphs on n nodes with exactly 3 connected components that are trees or cycles.

Terms

    a(0) =1a(1) =1a(2) =3a(3) =6a(4) =12a(5) =23a(6) =47a(7) =92a(8) =189a(9) =401a(10) =869a(11) =1949a(12) =4475a(13) =10520a(14) =25183a(15) =61366a(16) =151555a(17) =379164a(18) =958555a(19) =2446746a(20) =6296819a(21) =16326996a(22) =42613240a(23) =111889355a(24) =295372835a(25) =783598713a(26) =2088175182a(27) =5587741350a(28) =15009229137a(29) =40458659246

External references