A224747 - cp's OEIS frontend

A224747 Number of lattice paths from (0,0) to (n,0) that do not go below the x-axis and consist of steps U=(1,1), D=(1,-1) and H=(1,0), where H-steps are only allowed if y=1.

n	a(n)
0	1
1	0
2	1
3	1
4	3
5	5
6	12
7	23
8	52
9	105
10	232
11	480
12	1049
13	2199
14	4777
15	10092
16	21845
17	46377
18	100159
19	213328
20	460023
21	981976
22	2115350
23	4522529
24	9735205
25	20836827
26	44829766
27	96030613
28	206526972
29	442675064
30	951759621
31	2040962281
32	4387156587
33	9411145925
34	20226421380

[1, 0, 1, 1, 3, 5, 12, 23, 52, 105, 232, 480, 1049, 2199, 4777, 10092, 21845, 46377, 100159, 213328, 460023, 981976, 2115350, 4522529, 9735205, 20836827, 44829766, 96030613, 206526972, 442675064, 951759621, 2040962281, 4387156587, 9411145925, 20226421380]

cp's OEIS Frontend

A224747 Number of lattice paths from (0,0) to (n,0) that do not go below the x-axis and consist of steps U=(1,1), D=(1,-1) and H=(1,0), where H-steps are only allowed if y=1.

Table of values

List of values