A121139 Numbers of isomers of unbranched a-4-catapolyheptagons - see Brunvoll reference for precise definition.

1, 3, 11, 48, 228, 1080, 5112, 23920, 110848

Offset

2,2

References

J. Brunvoll, S. J. Cyvin and B. N. Cyvin, Isomer enumeration of polygonal systems..., J. Molec. Struct. (Theochem), 364 (1996), 1-13.

Links

Table of n, a(n) for n=2..10.

Crossrefs

Sequence in context: A308538 A181278 A126180 * A316703 A362741 A192399

Adjacent sequences: A121136 A121137 A121138 * A121140 A121141 A121142

Keyword

nonn

Author

N. J. A. Sloane, Aug 13 2006

Status

approved