

A038144


Number of planar nhexes, or polyhexes (in the sense of A000228, so rotations and reflections count as the same shape) with at least one hole.


5



0, 0, 0, 0, 0, 1, 2, 13, 67, 404, 2323, 13517, 76570, 429320, 2373965, 13004323, 70641985, 381260615, 2046521491, 10936624026, 58228136539
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OFFSET

1,7


COMMENTS

Apparently the same as the number of hexagonal planar circulenes (planar rings of hexagons) with n cells, although the two sequences may in fact differ for large n.


REFERENCES

J. V. Knop et al., On the total number of polyhexes, Match, No. 16 (1984), 119134.


LINKS



CROSSREFS



KEYWORD

nonn


AUTHOR



EXTENSIONS

More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), May 05 2007


STATUS

approved



