OFFSET
1,3
COMMENTS
See A003120 for definitions.
LINKS
J.-C. Arditti, Dénombrement des arborescences dont le graphe de comparabilité est Hamiltonien, Discrete Math., 5 (1973), 189-200.
EXAMPLE
Triangle begins:
1
1
2
3, 1
7, 1, 1
13, 5, 1, 1
31, 9, 6, 1, 1
66, 29, 11, 7, 1, 1
159, 62, 42, 13, 8, 1, 1
365, 181, 92, 55, 15, 9, 1, 1
900, 422, 294, 127, 70, 17, 10, 1, 1
2162, 1166, 720, 435, 165, 86, 19, 11, 1, 1
5417, 2885, 2119, 1110, 608, 208, 104, 21, 12, 1, 1
...
CROSSREFS
KEYWORD
nonn,tabf
AUTHOR
N. J. A. Sloane, Jul 27 2011
STATUS
approved