A109158 - cp's OEIS frontend

A109158 Triangle read by rows: T(n,k) is number of paths from (0,0) to (3n,0) that stay in the first quadrant (but may touch the horizontal axis), consisting of steps u=(2,1),U=(1,2), or d=(1,-1) and having height of last peak equal to k.

n	a(n)
1	1
2	1
3	2
4	4
5	3
6	1
7	10
8	20
9	18
10	12
11	5
12	1
13	66
14	132
15	122
16	92
17	54
18	24
19	7
20	1
21	498
22	996
23	930
24	732
25	478
26	264
27	118
28	40
29	9
30	1
31	4066
32	8132
33	7634
34	6140
35	4214
36	2552
37	1342
38	600
39	218
40	60
41	11
42	1
43	34970
44	69940
45	65874
46	53676
47	37910
48	24136
49	13782
50	7016
51	3122
52	1180
53	362
54	84
55	13
56	1

[1, 1, 2, 4, 3, 1, 10, 20, 18, 12, 5, 1, 66, 132, 122, 92, 54, 24, 7, 1, 498, 996, 930, 732, 478, 264, 118, 40, 9, 1, 4066, 8132, 7634, 6140, 4214, 2552, 1342, 600, 218, 60, 11, 1, 34970, 69940, 65874, 53676, 37910, 24136, 13782, 7016, 3122, 1180, 362, 84, 13, 1]

cp's OEIS Frontend

A109158 Triangle read by rows: T(n,k) is number of paths from (0,0) to (3n,0) that stay in the first quadrant (but may touch the horizontal axis), consisting of steps u=(2,1),U=(1,2), or d=(1,-1) and having height of last peak equal to k.

Table of values

List of values