A317184 Number of "non-connected" chord diagrams of degree n.

0, 1, 3, 12, 74, 647, 6961, 89739, 1337152, 22609111, 427604861, 8945156182, 205080060435, 5113424483894, 137759755603055, 3987742282544259, 123430664010624370, 4067922952436728611, 142218912116692593949

Offset: 1

Author

N. J. A. Sloane, Jul 26 2018

Keywords

• nonn

Links

• Alexander Stoimenow, On the number of chord diagrams, Discr. Math. 218 (2000), 209-233.

Crossrefs

Cf. A005034, A018225.

Programs

Mathematica

Stoimenow states that a Mma package is available from his website.

Extensions

More terms from Sean A. Irvine, Feb 04 2019