OFFSET
2,4
LINKS
S. J. Cyvin, J. Brunvoll, and B. N. Cyvin, Enumeration of unbranched catacondensed polygonal systems: general solution for two kinds of polygons, Journal of Chemical Information and Computer Sciences, 37 (1997), 460-466. See Table 7.
EXAMPLE
Triangle begins:
1, 2, 1,
4, 11, 10, 3,
16, 56, 73, 42, 9,
64, 272, 460, 387, 162, 27,
...
CROSSREFS
KEYWORD
nonn,tabf,more
AUTHOR
N. J. A. Sloane, Feb 09 2019
STATUS
approved