A360882 Number of unlabeled connected multigraphs with n edges, no cut-points and degree >= 3 at each node, loops allowed.

0, 1, 3, 5, 10, 21, 45, 114, 330, 1045, 3623, 13545, 53597, 223085, 969159

Offset

1,3

Links

Table of n, a(n) for n=1..15.

Formula

a(n) = A360871(n) + 1 for n > 1.

Example

The a(3) = 3 multigraphs are:
  - a single vertex with 3 loops;
  - a triple edge;
  - a single edge with a loop at each vertex.

Crossrefs

Cf. A002935, A360863, A360867, A360871.

Row sums of A360870.

Sequence in context: A284237 A241436 A018107 * A053709 A102772 A018005

Adjacent sequences: A360879 A360880 A360881 * A360883 A360884 A360885

Keyword

nonn,more

Author

Andrew Howroyd, Feb 27 2023

Status

approved