A161788 - cp's OEIS frontend

A161788 a(n) is the largest integer of the form 2^k - 1 that divides n.

n	a(n)
1	1
2	1
3	3
4	1
5	1
6	3
7	7
8	1
9	3
10	1
11	1
12	3
13	1
14	7
15	15
16	1
17	1
18	3
19	1
20	1
21	7
22	1
23	1
24	3
25	1
26	1
27	3
28	7
29	1
30	15
31	31
32	1
33	3
34	1
35	7
36	3
37	1
38	1
39	3
40	1
41	1
42	7
43	1
44	1
45	15
46	1
47	1
48	3
49	7
50	1
51	3
52	1
53	1
54	3
55	1
56	7
57	3
58	1
59	1
60	15
61	1
62	31
63	63
64	1
65	1
66	3
67	1
68	1
69	3
70	7
71	1
72	3
73	1
74	1
75	15
76	1
77	7
78	3
79	1
80	1
81	3
82	1
83	1
84	7
85	1
86	1
87	3
88	1
89	1
90	15
91	7
92	1
93	31
94	1
95	1
96	3
97	1
98	7
99	3
100	1
101	1

[1, 1, 3, 1, 1, 3, 7, 1, 3, 1, 1, 3, 1, 7, 15, 1, 1, 3, 1, 1, 7, 1, 1, 3, 1, 1, 3, 7, 1, 15, 31, 1, 3, 1, 7, 3, 1, 1, 3, 1, 1, 7, 1, 1, 15, 1, 1, 3, 7, 1, 3, 1, 1, 3, 1, 7, 3, 1, 1, 15, 1, 31, 63, 1, 1, 3, 1, 1, 3, 7, 1, 3, 1, 1, 15, 1, 7, 3, 1, 1, 3, 1, 1, 7, 1, 1, 3, 1, 1, 15, 7, 1, 31, 1, 1, 3, 1, 7, 3, 1, 1]

cp's OEIS Frontend

A161788 a(n) is the largest integer of the form 2^k - 1 that divides n.

Table of values

List of values

n	a(n)
1	1
2	1
3	3
4	1
5	1
6	3
7	7
8	1
9	3
10	1
11	1
12	3
13	1
14	7
15	15
16	1
17	1
18	3
19	1
20	1
21	7
22	1
23	1
24	3
25	1
26	1
27	3
28	7
29	1
30	15
31	31
32	1
33	3
34	1
35	7
36	3
37	1
38	1
39	3
40	1
41	1
42	7
43	1
44	1
45	15
46	1
47	1
48	3
49	7
50	1
51	3
52	1
53	1
54	3
55	1
56	7
57	3
58	1
59	1
60	15
61	1
62	31
63	63
64	1
65	1
66	3
67	1
68	1
69	3
70	7
71	1
72	3
73	1
74	1
75	15
76	1
77	7
78	3
79	1
80	1
81	3
82	1
83	1
84	7
85	1
86	1
87	3
88	1
89	1
90	15
91	7
92	1
93	31
94	1
95	1
96	3
97	1
98	7
99	3
100	1
101	1

n	a(n)
1	1
2	1
3	3
4	1
5	1
6	3
7	7
8	1
9	3
10	1
11	1
12	3
13	1
14	7
15	15
16	1
17	1
18	3
19	1
20	1
21	7
22	1
23	1
24	3
25	1
26	1
27	3
28	7
29	1
30	15
31	31
32	1
33	3
34	1
35	7
36	3
37	1
38	1
39	3
40	1
41	1
42	7
43	1
44	1
45	15
46	1
47	1
48	3
49	7
50	1
51	3
52	1
53	1
54	3
55	1
56	7
57	3
58	1
59	1
60	15
61	1
62	31
63	63
64	1
65	1
66	3
67	1
68	1
69	3
70	7
71	1
72	3
73	1
74	1
75	15
76	1
77	7
78	3
79	1
80	1
81	3
82	1
83	1
84	7
85	1
86	1
87	3
88	1
89	1
90	15
91	7
92	1
93	31
94	1
95	1
96	3
97	1
98	7
99	3
100	1
101	1

n	a(n)
1	1
2	1
3	3
4	1
5	1
6	3
7	7
8	1
9	3
10	1
11	1
12	3
13	1
14	7
15	15
16	1
17	1
18	3
19	1
20	1
21	7
22	1
23	1
24	3
25	1
26	1
27	3
28	7
29	1
30	15
31	31
32	1
33	3
34	1
35	7
36	3
37	1
38	1
39	3
40	1
41	1
42	7
43	1
44	1
45	15
46	1
47	1
48	3
49	7
50	1
51	3
52	1
53	1
54	3
55	1
56	7
57	3
58	1
59	1
60	15
61	1
62	31
63	63
64	1
65	1
66	3
67	1
68	1
69	3
70	7
71	1
72	3
73	1
74	1
75	15
76	1
77	7
78	3
79	1
80	1
81	3
82	1
83	1
84	7
85	1
86	1
87	3
88	1
89	1
90	15
91	7
92	1
93	31
94	1
95	1
96	3
97	1
98	7
99	3
100	1
101	1