A203175 - cp's OEIS frontend

A203175 Number of nX2 0..2 arrays with every 1 immediately preceded by 0 to the left or above, no 0 immediately preceded by a 0, and every 2 immediately preceded by 0 1 to the left or above.

n	a(n)
1	1
2	1
3	2
4	4
5	6
6	10
7	18
8	30
9	50
10	86
11	146
12	246
13	418
14	710
15	1202
16	2038
17	3458
18	5862
19	9938
20	16854
21	28578
22	48454
23	82162
24	139318
25	236226
26	400550
27	679186
28	1151638
29	1952738
30	3311110
31	5614386
32	9519862
33	16142082
34	27370854
35	46410578
36	78694742
37	133436450
38	226257606

[1, 1, 2, 4, 6, 10, 18, 30, 50, 86, 146, 246, 418, 710, 1202, 2038, 3458, 5862, 9938, 16854, 28578, 48454, 82162, 139318, 236226, 400550, 679186, 1151638, 1952738, 3311110, 5614386, 9519862, 16142082, 27370854, 46410578, 78694742, 133436450, 226257606]

cp's OEIS Frontend

A203175 Number of nX2 0..2 arrays with every 1 immediately preceded by 0 to the left or above, no 0 immediately preceded by a 0, and every 2 immediately preceded by 0 1 to the left or above.

Table of values

List of values