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A204387
Triangle read by rows: T(n,k) (n >= 1, 2 <= k <= n-1) is number of non-crossing trees with k nodes and path-length n.
0
1, 0, 1, 0, 2, 1, 0, 0, 4, 1, 0, 0, 3, 6, 1, 0, 0, 4, 10, 8, 1, 0, 0, 0, 12, 21, 10, 1, 0, 0, 0, 12, 32, 28, 12, 1, 0, 0, 0, 6, 45
OFFSET
1,5
LINKS
E. Deutsch and M. Noy, Statistics on non-crossing trees, Discrete Math., 254 (2002), 75-87 (see Th. 6).
EXAMPLE
Triangle begins:
1
0 1
0 2 1
0 0 4 1
0 0 3 6 1
0 0 4 10 8 1
0 0 0 12 21 10 1
0 0 0 12 32 28 12 1
CROSSREFS
Sequence in context: A369195 A065719 A336087 * A110509 A113953 A319574
KEYWORD
nonn,tabl,more
AUTHOR
N. J. A. Sloane, Jan 17 2012
STATUS
approved