Number of binary search trees (BST) on n nodes which have the same height as the optimal BST.

Terms

a(0) =1a(1) =1a(2) =2a(3) =1a(4) =6a(5) =6a(6) =4a(7) =1a(8) =94a(9) =114a(10) =116a(11) =94a(12) =60a(13) =28a(14) =8a(15) =1a(16) =32398a(17) =41658a(18) =49700a(19) =54746a(20) =55308a(21) =50788a(22) =41944a(23) =30782a(24) =19788a(25) =10948a(26) =5096a(27) =1932a(28) =568a(29) =120