Triangle read by rows: T(n,k) = the number of Dyck paths of semilength n with k UDDU's.

Terms

a(0) =1a(1) =1a(2) =2a(3) =4a(4) =1a(5) =9a(6) =5a(7) =23a(8) =17a(9) =2a(10) =63a(11) =54a(12) =15a(13) =178a(14) =177a(15) =69a(16) =5a(17) =514a(18) =594a(19) =273a(20) =49a(21) =1515a(22) =1997a(23) =1056a(24) =280a(25) =14a(26) =4545a(27) =6698a(28) =4077a(29) =1308