A069466 - cp's OEIS frontend

A069466 Triangle T(n, k) of numbers of square lattice walks that start and end at origin after 2*n steps and contain exactly k steps to the east, possibly touching origin at intermediate stages.

n	a(n)
0	1
1	2
2	2
3	6
4	24
5	6
6	20
7	180
8	180
9	20
10	70
11	1120
12	2520
13	1120
14	70
15	252
16	6300
17	25200
18	25200
19	6300
20	252
21	924
22	33264
23	207900
24	369600
25	207900
26	33264
27	924
28	3432
29	168168
30	1513512
31	4204200
32	4204200
33	1513512
34	168168
35	3432
36	12870
37	823680
38	10090080
39	40360320
40	63063000
41	40360320
42	10090080
43	823680
44	12870

[1, 2, 2, 6, 24, 6, 20, 180, 180, 20, 70, 1120, 2520, 1120, 70, 252, 6300, 25200, 25200, 6300, 252, 924, 33264, 207900, 369600, 207900, 33264, 924, 3432, 168168, 1513512, 4204200, 4204200, 1513512, 168168, 3432, 12870, 823680, 10090080, 40360320, 63063000, 40360320, 10090080, 823680, 12870]

cp's OEIS Frontend

A069466 Triangle T(n, k) of numbers of square lattice walks that start and end at origin after 2*n steps and contain exactly k steps to the east, possibly touching origin at intermediate stages.

Table of values

List of values