A169774 - cp's OEIS frontend

A169774 Number of open knight's tour diagrams of a 3 X n chessboard that are symmetric under 180-degree rotation and have "type F": the endpoints occur in different columns and agree in color with the cells in the nearest corner.

n	a(n)
4	2
5	0
6	0
7	4
8	12
9	20
10	28
11	120
12	104
13	304
14	384
15	1304
16	1680
17	4936
18	5908
19	18304
20	21412
21	63440
22	76920
23	233248
24	281284
25	833720
26	990104
27	2993016
28	3523740
29	10485472
30	12432392
31	37485424
32	44184884
33	131430320
34	154630088
35	465106072
36	544994604
37	1622783328
38	1904647128

[2, 0, 0, 4, 12, 20, 28, 120, 104, 304, 384, 1304, 1680, 4936, 5908, 18304, 21412, 63440, 76920, 233248, 281284, 833720, 990104, 2993016, 3523740, 10485472, 12432392, 37485424, 44184884, 131430320, 154630088, 465106072, 544994604, 1622783328, 1904647128]

cp's OEIS Frontend

A169774 Number of open knight's tour diagrams of a 3 X n chessboard that are symmetric under 180-degree rotation and have "type F": the endpoints occur in different columns and agree in color with the cells in the nearest corner.

Table of values

List of values