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), 119-134.
LINKS
Craig Knecht, Tiling of a fixed pattern of holes in a frame.
J. V. Knop, K. Szymanski, Ž. Jeričević, and N. Trinajstić, On the total number of polyhexes, Match, No. 16 (1984), 119-134.
Joseph Myers, Polyomino, polyhex and polyiamond tiling
CROSSREFS
KEYWORD
nonn
AUTHOR
EXTENSIONS
More terms from Joseph Myers, May 05 2002
Further terms from Joseph Myers, Nov 06 2003
More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), May 05 2007
Link edited by Joseph Myers, Nov 17 2010
STATUS
approved