A121115 Related to enumeration of rooted catapolyoctagons (see Cyvin reference for precise definition).

0, 1, 10, 87, 742, 6355, 54972, 480676, 4246156, 37857609, 340321820, 3081805727, 28089617550, 257516093302, 2373098818888, 21971084873775, 204274300836144, 1906474633391853, 17854760020687254, 167745930396293263, 1580556744351118030, 14932307414985485049, 141420575129236412394

Offset

1,3

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, W_r.

Links

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

Formula

a(n) = Sum_{i=1..n-1} A036758(i)*A036758(n-i) [Cyvin eq. (18)]. - R. J. Mathar, Jul 31 2019

Crossrefs

Sequence in context: A251193 A198858 A331793 * A292998 A114648 A350134

Adjacent sequences: A121112 A121113 A121114 * A121116 A121117 A121118

Keyword

nonn

Author

N. J. A. Sloane, Aug 13, 2006

Status

approved