A054117 T(n,n-2), array T as in A054115.

1, 6, 30, 150, 870, 5910, 46230, 409110, 4037910, 43954710, 522956310, 6749977110, 93928268310, 1401602636310, 22324392524310, 378011820620310, 6780385526348310

Offset: 2

Author

Clark Kimberling

Keywords

• nonn

Links

• Jan Kneissler, The number of primitive Vassiliev invariants of degree up to 12, arXiv:q-alg/9706022, 1997; Section 6.1.

Formula

Conjecture: a(n) -(n+1)*a(n-1) +n*a(n-2)=0. - R. J. Mathar, Jun 13 2013