A221768 - OEIS

A221768 as a simple table

n	a(n)
1	0
2	0
3	0
4	0
5	1
6	0
7	0
8	3
9	3
10	0
11	0
12	8
13	16
14	8
15	0
16	0
17	21
18	92
19	92
20	21
21	0
22	0
23	55
24	536
25	1042
26	536
27	55
28	0
29	0
30	144
31	3125
32	12177
33	12177
34	3125
35	144
36	0
37	0
38	377
39	18216
40	141177
41	296912
42	141177
43	18216
44	377
45	0
46	0
47	987
48	106174
49	1635606
50	7115200
51	7115200
52	1635606
53	106174
54	987
55	0
56	0
57	2584

[0,0,0,0,1,0,0,3,3,0,0,8,16,8,0,0,21,92,92,21,0,0, 55,536,1042,536,55,0,0,144,3125,12177,12177,3125, 144,0,0,377,18216,141177,296912,141177,18216,377, 0,0,987,106174,1635606,7115200,7115200,1635606, 106174,987,0,0,2584]