Number of UU's (i.e., doublerises) in all skew Dyck paths of semilength n.

A128743

Number of UU's (i.e., doublerises) in all skew Dyck paths of semilength n.

Terms

    a(0) =0a(1) =0a(2) =2a(3) =13a(4) =69a(5) =346a(6) =1700a(7) =8286a(8) =40264a(9) =195488a(10) =949302a(11) =4613025a(12) =22436997a(13) =109240038a(14) =532410060a(15) =2597468685a(16) =12684628125a(17) =62002335160a(18) =303332650190

External references