Number of Dyck paths of semilength n such that at least one positive level has no peaks.

A288539

Number of Dyck paths of semilength n such that at least one positive level has no peaks.

Terms

    a(0) =1a(1) =0a(2) =1a(3) =2a(4) =8a(5) =25a(6) =83a(7) =282a(8) =971a(9) =3386a(10) =11940a(11) =42504a(12) =152546a(13) =551426a(14) =2005930a(15) =7337901a(16) =26976726a(17) =99618976a(18) =369349607a(19) =1374391706a(20) =5131186060a(21) =19214759396a(22) =72152791729a(23) =271629133830

External references