Triangle read by rows: T(n,k) is the number of Dyck paths of semilength n having exactly k UDU's at low level.

A098747

Triangle read by rows: T(n,k) is the number of Dyck paths of semilength n having exactly k UDU's at low level.

Terms

    a(0) =1a(1) =1a(2) =1a(3) =3a(4) =1a(5) =1a(6) =8a(7) =4a(8) =1a(9) =1a(10) =24a(11) =11a(12) =5a(13) =1a(14) =1a(15) =75a(16) =35a(17) =14a(18) =6a(19) =1a(20) =1a(21) =243a(22) =113a(23) =47a(24) =17a(25) =7a(26) =1a(27) =1a(28) =808a(29) =376

External references