A047753 - OEIS

A047753 as a simple table

n	a(n)
1	0
2	0
3	0
4	0
5	0
6	0
7	0
8	0
9	1
10	0
11	0
12	0
13	2
14	0
15	0
16	0
17	2
18	0
19	0
20	0
21	7
22	0
23	0
24	0
25	12
26	0
27	0
28	0
29	29
30	0
31	0
32	0
33	55
34	0
35	0
36	0
37	143
38	0
39	0
40	0
41	271
42	0
43	0
44	0
45	728
46	0
47	0
48	0
49	1428
50	0
51	0
52	0
53	3873
54	0
55	0
56	0
57	7752
58	0
59	0
60	0
61	21318
62	0
63	0
64	0
65	43256
66	0
67	0
68	0
69	120175
70	0
71	0
72	0
73	246675
74	0
75	0
76	0

[0,0,0,0,0,0,0,0,1,0,0,0,2,0,0,0,2,0,0,0,7,0,0,0, 12,0,0,0,29,0,0,0,55,0,0,0,143,0,0,0,271,0,0,0, 728,0,0,0,1428,0,0,0,3873,0,0,0,7752,0,0,0,21318, 0,0,0,43256,0,0,0,120175,0,0,0,246675,0,0,0]