Number of Dyck paths of semilength n such that every peak at level y > 1 is preceded by (at least) one peak at level y-1 and is followed by (at least) one peak at level y-1.
A287776
Number of Dyck paths of semilength n such that every peak at level y > 1 is preceded by (at least) one peak at level y-1 and is followed by (at least) one peak at level y-1.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =2a(5) =4a(6) =8a(7) =17a(8) =39a(9) =95a(10) =241a(11) =629a(12) =1679a(13) =4572a(14) =12684a(15) =35812a(16) =102774a(17) =299371a(18) =883848a(19) =2641121a(20) =7978262a(21) =24337821a(22) =74908008a(23) =232451921a(24) =726831776a(25) =2288799963a(26) =7255401745a(27) =23143158678a(28) =74256591422a(29) =239582207959
External references
- oeis: A287776