A290658 - OEIS

A290658 as a simple table

n	a(n)
0	1
1	1
2	1
3	1
4	3
5	3
6	3
7	3
8	3
9	11
10	15
11	15
12	15
13	15
14	15
15	15
16	15
17	15
18	15
19	239
20	255
21	255
22	255
23	255
24	255
25	255
26	255
27	255
28	255
29	255
30	255
31	255
32	255
33	1023
34	2047
35	59391
36	65535
37	65535
38	65535
39	65535
40	65535
41	65535
42	65535
43	65535
44	65535
45	65535
46	65535
47	65535
48	65535
49	65535

[1,1,1,1,3,3,3,3,3,11,15,15,15,15,15,15,15,15,15, 239,255,255,255,255,255,255,255,255,255,255,255, 255,255,1023,2047,59391,65535,65535,65535,65535, 65535,65535,65535,65535,65535,65535,65535,65535, 65535,65535]