Number of Dyck paths of semilength n having exactly 1 occurrence of the consecutive steps UDUUUDDDUD (with U=(1,1), D=(1,-1)).

A243871

Number of Dyck paths of semilength n having exactly 1 occurrence of the consecutive steps UDUUUDDDUD (with U=(1,1), D=(1,-1)).

Terms

    a(0) =1a(1) =3a(2) =10a(3) =35a(4) =124a(5) =454a(6) =1684a(7) =6305a(8) =23781a(9) =90209a(10) =343809a(11) =1315499a(12) =5050144a(13) =19442366a(14) =75034354a(15) =290203076a(16) =1124511549a(17) =4364693311a(18) =16966567970a(19) =66041815437a(20) =257378634365

External references