A334978 - cp's OEIS frontend

A334978 a(n) is the total number of down steps between the (n-1)-th and n-th up steps in all 3-Dyck paths of length 4*n. A 3-Dyck path is a nonnegative lattice path with steps (1, 3), (1, -1) that starts and ends at y = 0.

n	a(n)
0	0
1	0
2	6
3	52
4	409
5	3208
6	25484
7	205452
8	1679332
9	13894848
10	116193246
11	980658172
12	8343605534
13	71492410640
14	616418176920
15	5344364518140
16	46565472754044
17	407529832131712
18	3580911446989368
19	31579384975219920
20	279414033129153065
21	2479725948121016040

[0, 0, 6, 52, 409, 3208, 25484, 205452, 1679332, 13894848, 116193246, 980658172, 8343605534, 71492410640, 616418176920, 5344364518140, 46565472754044, 407529832131712, 3580911446989368, 31579384975219920, 279414033129153065, 2479725948121016040]

cp's OEIS Frontend

A334978 a(n) is the total number of down steps between the (n-1)-th and n-th up steps in all 3-Dyck paths of length 4*n. A 3-Dyck path is a nonnegative lattice path with steps (1, 3), (1, -1) that starts and ends at y = 0.

Table of values

List of values