A222907 - cp's OEIS frontend

A222907 Number of 2 X n 0..3 arrays with no more than floor(2 X n/2) elements unequal to at least one horizontal or antidiagonal neighbor, with new values introduced in row major 0..3 order.

n	a(n)
1	2
2	4
3	7
4	25
5	92
6	403
7	1710
8	8021
9	36160
10	175685
11	811796
12	3996105
13	18729552
14	92602363
15	438528764
16	2169839823
17	10361611742
18	51246105785
19	246397237188
20	1217744328605
21	5887982752143
22	29081428391143
23	141255777787573
24	697390129303759

[2, 4, 7, 25, 92, 403, 1710, 8021, 36160, 175685, 811796, 3996105, 18729552, 92602363, 438528764, 2169839823, 10361611742, 51246105785, 246397237188, 1217744328605, 5887982752143, 29081428391143, 141255777787573, 697390129303759]

cp's OEIS Frontend

A222907 Number of 2 X n 0..3 arrays with no more than floor(2 X n/2) elements unequal to at least one horizontal or antidiagonal neighbor, with new values introduced in row major 0..3 order.

Table of values

List of values