A018192 Number of chord diagrams of degree n with an isolated chord.

1, 1, 3, 11, 70, 607, 6577, 85198, 1276563, 21695178, 412195167, 8656676654, 199125735965, 4978810781633, 134447283590269, 3899543151272530, 120903273575624821, 3990362191131712939, 139681113828269665499, 5168844439275046565329

Offset

1,3

Links

Table of n, a(n) for n=1..20.

D. Bar-Natan, On the Vassiliev Knot Invariants, Topology 34 (1995) 423-472.

D. Bar-Natan, Bibliography of Vassiliev Invariants [Broken link]

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

Crossrefs

Sequence in context: A121945 A009025 A009103 * A056665 A345030 A378047

Adjacent sequences: A018189 A018190 A018191 * A018193 A018194 A018195

Keyword

nonn

Author

Alexander Stoimenow (stoimeno(AT)math.toronto.edu)

Extensions

More terms from Sean A. Irvine, Feb 04 2019

Status

approved