A169773 - cp's OEIS frontend

A169773 Number of open knight's tour diagrams of a 3 X n chessboard that are symmetric under 180-degree rotation and have "type X": both endpoints occur in the same column.

n	a(n)
4	0
5	0
6	0
7	0
8	0
9	4
10	0
11	0
12	0
13	16
14	0
15	0
16	0
17	264
18	0
19	0
20	0
21	2144
22	0
23	0
24	0
25	22408
26	0
27	0
28	0
29	211808
30	0
31	0
32	0
33	2087344
34	0
35	0
36	0
37	20207664
38	0
39	0
40	0
41	197082624
42	0
43	0
44	0
45	1916054112
46	0
47	0
48	0
49	18652927040
50	0
51	0
52	0
53	181485750208
54	0
55	0
56	0
57	1766199186560
58	0
59	0
60	0

[0, 0, 0, 0, 0, 4, 0, 0, 0, 16, 0, 0, 0, 264, 0, 0, 0, 2144, 0, 0, 0, 22408, 0, 0, 0, 211808, 0, 0, 0, 2087344, 0, 0, 0, 20207664, 0, 0, 0, 197082624, 0, 0, 0, 1916054112, 0, 0, 0, 18652927040, 0, 0, 0, 181485750208, 0, 0, 0, 1766199186560, 0, 0, 0]

cp's OEIS Frontend

A169773 Number of open knight's tour diagrams of a 3 X n chessboard that are symmetric under 180-degree rotation and have "type X": both endpoints occur in the same column.

Table of values

List of values