A215768 Number of undirected labeled graphs on n nodes with exactly 8 cycle graphs as connected components.

1, 36, 750, 12540, 195459, 3057912, 49471708, 835659825, 14779601837, 273850769192, 5313937212402, 107889695430426, 2289283137461287, 50700986253094800, 1170451253565199375, 28127697404018935030, 702741240223958509651, 18230243438652550293450

Offset: 8

Author

Alois P. Heinz, Aug 23 2012

Keywords

• nonn

Links

• Alois P. Heinz, Table of n, a(n) for n = 8..170

Crossrefs

Column k=8 of A215771.

Programs

Maple

T:= proc(n, k) option remember; `if`(k<0 or k>n, 0, `if`(n=0, 1,
      add(binomial(n-1, i)*T(n-1-i, k-1)*ceil(i!/2), i=0..n-k)))
    end:
a:= n-> T(n, 8):
seq (a(n), n=8..30);