Number of Dyck paths with no UUU's and no DDD's of semilength n and having k UUDD's (0<=k<=floor(n/2); U=(1,1), D=(1,-1)).

A166284

Number of Dyck paths with no UUU's and no DDD's of semilength n and having k UUDD's (0<=k<=floor(n/2); U=(1,1), D=(1,-1)).

Terms

    a(0) =1a(1) =1a(2) =1a(3) =1a(4) =2a(5) =2a(6) =4a(7) =3a(8) =1a(9) =7a(10) =7a(11) =3a(12) =13a(13) =17a(14) =6a(15) =1a(16) =26a(17) =36a(18) =16a(19) =4a(20) =52a(21) =77a(22) =45a(23) =10a(24) =1a(25) =104a(26) =173a(27) =111a(28) =30a(29) =5

External references