A293922 Number of linear chord diagrams having n chords and minimal chord length nine.

1, 639, 69676, 4100988, 184283856, 7306919616, 275875184700, 10345618038532, 394140369614751, 15439822086531614, 625906719760828175, 26339564820084748490, 1152078058596976970932, 52386933718575091061064, 2475581777015155231108104, 121493777824620584462513636

Offset: 9

Author

Alois P. Heinz, Oct 19 2017

Keywords

• nonn

Links

• Alois P. Heinz, Table of n, a(n) for n = 9..200

Crossrefs

Column k=9 of A293881.

Formula

a(n) ~ (exp(-8) - exp(-9)) * 2^(n + 1/2) * n^n / exp(n). - Vaclav Kotesovec, Oct 25 2017