a(n) is the total number of down steps between the second and third up steps in all 3_1-Dyck paths of length 4*n.
A334648
a(n) is the total number of down steps between the second and third up steps in all 3_1-Dyck paths of length 4*n.
Terms
- a(0) =0a(1) =0a(2) =34a(3) =132a(4) =722a(5) =4638a(6) =32416a(7) =238956a(8) =1827918a(9) =14370595a(10) =115384756a(11) =942115942a(12) =7798224226a(13) =65286060253a(14) =551838621972
External references
- oeis: A334648