A360879 Number of unlabeled nonseparable (or 2-connected) loopless multigraphs with circuit rank n and degree >= 3 at each node.

0, 1, 4, 17, 118, 1198, 17133

Offset

1,3

Links

Table of n, a(n) for n=1..7.

Formula

a(n) = Sum_{k=2..2*n-2} A046752(n + k - 1, k).

Crossrefs

Diagonal sums of A046752.

Cf. A002935, A360864.

Sequence in context: A271612 A240323 A335945 * A206353 A260694 A032115

Adjacent sequences: A360876 A360877 A360878 * A360880 A360881 A360882

Keyword

nonn,more

Author

Andrew Howroyd, Feb 25 2023

Status

approved