A027225 a(n) = Sum_{k=0..n-2} T(n,k) * T(n,k+2), with T given by A026747.

1, 8, 52, 247, 1416, 6056, 33731, 139016, 770116, 3121259, 17335095, 69642995, 388958218, 1554558921, 8740670953, 34818606079, 197136480944, 783522002716, 4466326137854, 17722654061673, 101674164224552, 402960855102206, 2325563749837462, 9208279020729297, 53433859702165884

Offset

2,2

Links

Table of n, a(n) for n=2..26.

Crossrefs

Sequence in context: A303509 A107584 A323940 * A073377 A055283 A193427

Adjacent sequences: A027222 A027223 A027224 * A027226 A027227 A027228

Keyword

nonn

Author

Clark Kimberling

Extensions

More terms from Sean A. Irvine, Oct 24 2019

Status

approved