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A101489 Square array T(n,k), read by antidiagonals: number of binary trees, with n nodes that have no label greater than k. 1
1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 1, 1, 2, 4, 4, 1, 1, 2, 5, 10, 10, 1, 1, 2, 5, 13, 26, 26, 1, 1, 2, 5, 14, 37, 73, 73, 1, 1, 2, 5, 14, 41, 109, 213, 213, 1, 1, 2, 5, 14, 42, 126, 334, 645, 645, 1, 1, 2, 5, 14, 42, 131, 398, 1050, 2007, 2007, 1, 1, 2, 5, 14, 42, 132, 422, 1289, 3377 (list; table; graph; refs; listen; history; internal format)
OFFSET

0,9

LINKS

M. Bousquet-Melou, Limit laws for embedded trees

FORMULA

G.f. of k-th row: A(t)=B(t)*(1-C(t)^(k+2))*(1-C(t)^(k+7))/[(1-C(t)^(k+4))*(1-C(t)^(k+5))], with B(t) the g.f. of A000108 and C(t) the g.f. of A101490.

EXAMPLE

1,1,1,2,4,10,26,73,213,645,

1,1,2,4,10,26,73,213,645,2007,

1,1,2,5,13,37,109,334,1050,3377,

1,1,2,5,14,41,126,398,1289,4253,

1,1,2,5,14,42,131,422,1390,4664,

1,1,2,5,14,42,132,428,1422,4812,

1,1,2,5,14,42,132,429,1429,4853,

1,1,2,5,14,42,132,429,1430,4861,

CROSSREFS

Rows converge to A000108. First row is A101488.

Sequence in context: A059260 A135229 A081372 * A104156 A070166 A131373

Adjacent sequences:  A101486 A101487 A101488 * A101490 A101491 A101492

KEYWORD

nonn,tabl

AUTHOR

Ralf Stephan, Jan 21 2005

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Last modified February 17 14:50 EST 2012. Contains 206050 sequences.