Number of Dyck paths of semilength n such that neighboring peaks differ in height by at most one and first and last peak are at height one.

A371726

Number of Dyck paths of semilength n such that neighboring peaks differ in height by at most one and first and last peak are at height one.

Terms

    a(0) =1a(1) =1a(2) =1a(3) =1a(4) =2a(5) =4a(6) =8a(7) =17a(8) =39a(9) =93a(10) =227a(11) =567a(12) =1447a(13) =3760a(14) =9917a(15) =26492a(16) =71567a(17) =195256a(18) =537397a(19) =1490614a(20) =4163508a(21) =11702411a(22) =33078992a(23) =93986117a(24) =268294604a(25) =769171970a(26) =2213834911a(27) =6395017291a(28) =18534987580a(29) =53887644375

External references