A121118 Related to enumeration of rooted catapolyoctagons (see Cyvin reference for precise definition).

0, 1, 2, 7, 14, 47, 100, 340, 756, 2605, 5972, 20799, 48750, 171218, 408088, 1442943, 3484480, 12388309, 30231806, 107971435, 265768846, 952810089, 2362256162, 8496532384, 21193912716, 76443985912, 191684088026, 693071685268

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 Z_r.

Links

Table of n, a(n) for n=1..28.

Formula

a(n) = Sum_{i=1..n-1} A036759(i)*A036759(n-i) [Cyvin eq. (30)] . - R. J. Mathar, Jul 31 2019

Crossrefs

Sequence in context: A329115 A018542 A018577 * A128882 A018281 A018592

Adjacent sequences: A121115 A121116 A121117 * A121119 A121120 A121121

Keyword

nonn

Author

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

Status

approved