A038141 Number of planar polyhexes with n cells with at least two holes, all holes having size at least two.

0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 11, 149, 1618, 15123, 125764

Offset

1,14

Comments

Planar, proper multiple coronoid systems enumerated by area. Free systems are enumerated, i.e., translations, rotations and reflections are regarded as the same configuration.

The last term includes 4 polyhexes with three holes.

References

S. J. Cyvin, J. Brunvoll, R. S. Chen, B. N. Cyvin, F. J. Zhang, Theory of Coronoid Hydrocarbons II, Lecture Notes in Chemistry 62, Springer-Verlag, 1994. (see table 3.2, p. 66)

Links

Table of n, a(n) for n=1..18.

J. V. Knop et al., Use of small computers for large computations: enumeration of polyhex hydrocarbons, J. Chem. Inf. Comput. Sci., 30 (1990), 159-160.

Crossrefs

Cf. A018190.

Cf. A000228 (hexagonal free polyominoes), A038140 (planar single coronoids).

Sequence in context: A261536 A175635 A103544 * A307072 A142083 A205085

Adjacent sequences: A038138 A038139 A038140 * A038142 A038143 A038144

Keyword

nonn,more

Author

N. J. A. Sloane.

Extensions

Edited by Markus Voege (markus.voege(AT)inria.fr), Dec 03 2003

Status

approved