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A065329 Square array read by antidiagonals giving number of binary trees of height n with k points on the n-th level (n,k>0). 3
1, 0, 2, 0, 1, 8, 0, 0, 8, 80, 0, 0, 4, 144, 4160, 0, 0, 1, 168, 13888, 5632640, 0, 0, 0, 138, 31776, 36109952, 5163215782400, 0, 0, 0, 80, 54792, 158572864, 64827181969920 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..35.

H. Bottomley, Illustration of initial terms

FORMULA

T(n, k)=Sum_j{2j >= k}[C(2j, k)*T(n-1, j)] starting with T(1, 1)=1 and T(1, k)=0 if k>1

EXAMPLE

Rows start (1,0,0,...), (2,1,0,0,...), (8,8,4,1,0,0,...), (80,144,168,138,80,32,8,1,0,0,...) etc.

CROSSREFS

Row sums are A001699. Cf. A073345 (A073429).

Sequence in context: A078341 A199459 A316649 * A108998 A309993 A248673

Adjacent sequences:  A065326 A065327 A065328 * A065330 A065331 A065332

KEYWORD

nonn,tabl

AUTHOR

Henry Bottomley, Oct 29 2001

STATUS

approved

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Last modified December 12 07:00 EST 2019. Contains 329948 sequences. (Running on oeis4.)