This site is supported by donations to The OEIS Foundation.

 Please make a donation to keep the OEIS running. We are now in our 55th year. In the past year we added 12000 new sequences and reached 8000 citations (which often say "discovered thanks to the OEIS"). We need to raise money to hire someone to manage submissions, which would reduce the load on our editors and speed up editing. Other ways to donate

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 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 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

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

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