A121117 Related to enumeration of rooted catapolyoctagons (see Cyvin reference for precise definition).

0, 0, 0, 1, 20, 274, 3224, 35119, 366152, 3717126, 37101780, 366240435, 3588644268, 34989880068, 340028122980, 3297155317612, 31927270515392, 308907360676012, 2987556153506904, 28890414890866473, 279405472916899476, 2702885116291760036, 26156597304381215188

Offset

1,5

References

S. J. Cyvin, B. N. Cyvin, and J. Brunvoll. Enumeration of tree-like octagonal systems: catapolyoctagons, ACH Models in Chem. 134 (1997), 55-70, Table III, Y_r.

Links

Table of n, a(n) for n=1..23.

Formula

a(n) = Sum_{i=1..n-3} A036758(i)*A121116(n-i) [Cyvin eq. (20)] . - R. J. Mathar, Jul 31 2019

Crossrefs

Sequence in context: A307038 A019613 A021514 * A278722 A021264 A025928

Adjacent sequences: A121114 A121115 A121116 * A121118 A121119 A121120

Keyword

nonn

Author

N. J. A. Sloane, Aug 13 2006

Status

approved