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

Author

Andrew Howroyd, Feb 27 2023

Keywords

• nonn
• more

Examples

			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.

Formula

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