a(n) is the total number of down steps between the 3rd and 4th up steps in all 2-Dyck paths of length 3*n.
A334641
a(n) is the total number of down steps between the 3rd and 4th up steps in all 2-Dyck paths of length 3*n.
Terms
- a(0) =0a(1) =0a(2) =0a(3) =43a(4) =108a(5) =444a(6) =2099a(7) =10683a(8) =56994a(9) =314296a(10) =1776519a(11) =10236081a(12) =59892690a(13) =354886920a(14) =2125117332a(15) =12839859620a(16) =78176677734a(17) =479177993904
External references
- oeis: A334641