Number of double rises in all left factors of Dyck paths of length n (a double rise consists of two consecutive (1,1)-steps).

A191524

Number of double rises in all left factors of Dyck paths of length n (a double rise consists of two consecutive (1,1)-steps).

Terms

    a(0) =0a(1) =0a(2) =1a(3) =3a(4) =8a(5) =18a(6) =42a(7) =89a(8) =198a(9) =410a(10) =890a(11) =1822a(12) =3896a(13) =7924a(14) =16772a(15) =33973a(16) =71378a(17) =144186a(18) =301242a(19) =607346a(20) =1263312a(21) =2543420a(22) =5271596a(23) =10601978a(24) =21909388a(25) =44026788a(26) =90757732a(27) =182258364a(28) =374917328a(29) =752509096

External references