A360881 Number of unlabeled nonseparable (or 2-connected) multigraphs with n edges, loops allowed.

1, 2, 5, 9, 19, 44, 111, 328, 1090, 3988, 15838, 67295, 301417, 1412821, 6882398, 34682721, 180170661, 962288228, 5273162329

Offset

1,2

Links

Table of n, a(n) for n=1..19.

Crossrefs

Row sums of A360880.

Cf. A007717, A007719, A010357.

Sequence in context: A320172 A350243 A079117 * A030137 A243080 A105309

Adjacent sequences: A360878 A360879 A360880 * A360882 A360883 A360884

Keyword

nonn,more

Author

Andrew Howroyd, Feb 25 2023

Status

approved