A323923 Branched catafusenes (cata-condensed benzenoids) without helicenes, symmetry C_s.

0, 1, 7, 44, 206, 937, 3997, 16719, 68520, 278239, 1121632, 4504875

Offset

4,3

Links

Table of n, a(n) for n=4..15.

A. T. Balaban, J. Brunvoll, B. N. Cyvin, and S. J. Cyvin, Enumeration of branched catacondensed benzenoid hydrocarbons and their numbers of Kekulé structures, Tetrahedron 44(1) (1988), 221-228. See Table 2.

Björg N. Cyvin, Jon Brunvoll and Sven J. Cyvin, Enumeration of benzenoid systems and other polyhexes, p. 65-180 in: I. Gutman (ed.), Advances in the Theory of Benzenoid Hydrocarbons II, Springer, 1992.

Crossrefs

For any symmetry, see A323851.

Sequence in context: A165210 A162454 A203210 * A026116 A216237 A291388

Adjacent sequences: A323920 A323921 A323922 * A323924 A323925 A323926

Keyword

nonn,more

Author

N. J. A. Sloane, Feb 09 2019

Extensions

Name clarified, a(13)-a(15) from Cyvin, Brunvoll & Cyvin (Table 17) added by Andrey Zabolotskiy, Feb 16 2023

Status

approved