Irregular triangle T(n,k) read by rows: number of orbits of size 2^k on Dyck n-paths.

Terms

a(0) =1a(1) =2a(2) =3a(3) =1a(4) =6a(5) =2a(6) =1a(7) =12a(8) =7a(9) =4a(10) =26a(11) =23a(12) =11a(13) =2a(14) =59a(15) =71a(16) =41a(17) =8a(18) =138a(19) =224a(20) =151a(21) =30a(22) =332a(23) =709a(24) =550a(25) =114a(26) =814a(27) =2253a(28) =1993a(29) =406