A108433 - cp's OEIS frontend

A108433 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 have k hills of the form ud (a hill is either a ud or a Udd starting at the x-axis).

n	a(n)
0	1
1	1
2	1
3	7
4	2
5	1
6	47
7	15
8	3
9	1
10	361
11	108
12	24
13	4
14	1
15	2977
16	865
17	184
18	34
19	5
20	1
21	25775
22	7334
23	1533
24	276
25	45
26	6
27	1
28	231103
29	64767
30	13359
31	2387
32	385
33	57
34	7
35	1
36	2127409
37	589368
38	120376
39	21368
40	3450
41	512
42	70
43	8
44	1
45	19990241
46	5488033
47	1112424
48	196484
49	31706

[1, 1, 1, 7, 2, 1, 47, 15, 3, 1, 361, 108, 24, 4, 1, 2977, 865, 184, 34, 5, 1, 25775, 7334, 1533, 276, 45, 6, 1, 231103, 64767, 13359, 2387, 385, 57, 7, 1, 2127409, 589368, 120376, 21368, 3450, 512, 70, 8, 1, 19990241, 5488033, 1112424, 196484, 31706]

cp's OEIS Frontend

A108433 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 have k hills of the form ud (a hill is either a ud or a Udd starting at the x-axis).

Table of values

List of values