A281738 - OEIS

A281738 as a simple table

n	a(n)
0	1
1	3
2	1
3	7
4	17
5	39
6	65
7	199
8	65
9	455
10	1025
11	2055
12	4097
13	8199
14	16385
15	32775
16	65537
17	131079
18	262145
19	524295
20	1048577
21	2097159
22	4194305
23	12582919
24	1
25	7
26	1
27	7
28	1
29	7
30	1
31	7
32	1
33	7
34	1
35	7
36	1
37	7
38	1
39	7
40	1
41	7
42	1
43	7
44	1
45	7
46	1
47	7
48	1
49	7
50	1
51	7
52	1
53	7
54	1
55	7
56	1
57	7
58	1
59	7
60	1
61	7

[1,3,1,7,17,39,65,199,65,455,1025,2055,4097,8199, 16385,32775,65537,131079,262145,524295,1048577, 2097159,4194305,12582919,1,7,1,7,1,7,1,7,1,7,1,7, 1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1, 7]

[1,3,1,7,17,39,65,199,65,455,1025,2055,4097,8199,
 16385,32775,65537,131079,262145,524295,1048577,
 2097159,4194305,12582919,1,7,1,7,1,7,1,7,1,7,1,7,
 1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,
 7]