A038143 Hexagonal cata-condensed helicenes with n cells (non-planar cata-fused benzenoid hydrocarbons).

0, 0, 0, 0, 0, 1, 5, 35, 200, 1121, 5919, 30509, 153187, 756825, 3688195

Offset

1,7

Links

Table of n, a(n) for n=1..15.

J. V. Knop, K. Szymanski, Ž. Jeričević, and N. Trinajstić, On the total number of polyhexes, Match, No. 16 (1984), 119-134.

Crossrefs

Equals A002216-A038142. Cf. A018190.

Sequence in context: A241779 A265976 A123008 * A352404 A356391 A221578

Adjacent sequences: A038140 A038141 A038142 * A038144 A038145 A038146

Keyword

nonn,more

Author

N. J. A. Sloane

Extensions

a(12)-a(15) from Andrey Zabolotskiy, Feb 16 2023

Status

approved