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.

A287709

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.

Terms

    a(0) =1a(1) =1a(2) =1a(3) =2a(4) =4a(5) =9a(6) =22a(7) =57a(8) =154a(9) =430a(10) =1234a(11) =3625a(12) =10865a(13) =33136a(14) =102598a(15) =321913a(16) =1021963a(17) =3278543a(18) =10617413a(19) =34678693a(20) =114151769a(21) =378436049a(22) =1262822229a(23) =4239469076a(24) =14312153289a(25) =48567846377a(26) =165610404277a(27) =567259571451

External references