A379127 - cp's OEIS frontend

A379127 a(1) = 1; for n > 1, a(n) is the largest proper divisor d of 2n-1 such that A048720(A065621(d),(2n-1)/d) is equal to 2n-1.

n	a(n)
1	1
2	1
3	1
4	1
5	3
6	1
7	1
8	1
9	1
10	1
11	3
12	1
13	1
14	1
15	1
16	1
17	11
18	5
19	1
20	1
21	1
22	1
23	3
24	1
25	7
26	1
27	1
28	1
29	1
30	1
31	1
32	1
33	13
34	1
35	1
36	1
37	1
38	5
39	1
40	1
41	1
42	1
43	1
44	1
45	1
46	1
47	3
48	1
49	1
50	1
51	1
52	1
53	7
54	1
55	1
56	1
57	1
58	1
59	1
60	1
61	1
62	1
63	1
64	1
65	43
66	1
67	19
68	9
69	1
70	1
71	1
72	1
73	1
74	1
75	1
76	1
77	3
78	5
79	1
80	1
81	23
82	1
83	11
84	1
85	1
86	1
87	1
88	1
89	1
90	1
91	1
92	1
93	1
94	1
95	3
96	1
97	1
98	13
99	1
100	1
101	1
102	1
103	1
104	1
105	1

[1, 1, 1, 1, 3, 1, 1, 1, 1, 1, 3, 1, 1, 1, 1, 1, 11, 5, 1, 1, 1, 1, 3, 1, 7, 1, 1, 1, 1, 1, 1, 1, 13, 1, 1, 1, 1, 5, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 1, 1, 7, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 43, 1, 19, 9, 1, 1, 1, 1, 1, 1, 1, 1, 3, 5, 1, 1, 23, 1, 11, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 13, 1, 1, 1, 1, 1, 1, 1]

cp's OEIS Frontend

A379127 a(1) = 1; for n > 1, a(n) is the largest proper divisor d of 2n-1 such that A048720(A065621(d),(2n-1)/d) is equal to 2n-1.

Table of values

List of values

n	a(n)
1	1
2	1
3	1
4	1
5	3
6	1
7	1
8	1
9	1
10	1
11	3
12	1
13	1
14	1
15	1
16	1
17	11
18	5
19	1
20	1
21	1
22	1
23	3
24	1
25	7
26	1
27	1
28	1
29	1
30	1
31	1
32	1
33	13
34	1
35	1
36	1
37	1
38	5
39	1
40	1
41	1
42	1
43	1
44	1
45	1
46	1
47	3
48	1
49	1
50	1
51	1
52	1
53	7
54	1
55	1
56	1
57	1
58	1
59	1
60	1
61	1
62	1
63	1
64	1
65	43
66	1
67	19
68	9
69	1
70	1
71	1
72	1
73	1
74	1
75	1
76	1
77	3
78	5
79	1
80	1
81	23
82	1
83	11
84	1
85	1
86	1
87	1
88	1
89	1
90	1
91	1
92	1
93	1
94	1
95	3
96	1
97	1
98	13
99	1
100	1
101	1
102	1
103	1
104	1
105	1

n	a(n)
1	1
2	1
3	1
4	1
5	3
6	1
7	1
8	1
9	1
10	1
11	3
12	1
13	1
14	1
15	1
16	1
17	11
18	5
19	1
20	1
21	1
22	1
23	3
24	1
25	7
26	1
27	1
28	1
29	1
30	1
31	1
32	1
33	13
34	1
35	1
36	1
37	1
38	5
39	1
40	1
41	1
42	1
43	1
44	1
45	1
46	1
47	3
48	1
49	1
50	1
51	1
52	1
53	7
54	1
55	1
56	1
57	1
58	1
59	1
60	1
61	1
62	1
63	1
64	1
65	43
66	1
67	19
68	9
69	1
70	1
71	1
72	1
73	1
74	1
75	1
76	1
77	3
78	5
79	1
80	1
81	23
82	1
83	11
84	1
85	1
86	1
87	1
88	1
89	1
90	1
91	1
92	1
93	1
94	1
95	3
96	1
97	1
98	13
99	1
100	1
101	1
102	1
103	1
104	1
105	1

n	a(n)
1	1
2	1
3	1
4	1
5	3
6	1
7	1
8	1
9	1
10	1
11	3
12	1
13	1
14	1
15	1
16	1
17	11
18	5
19	1
20	1
21	1
22	1
23	3
24	1
25	7
26	1
27	1
28	1
29	1
30	1
31	1
32	1
33	13
34	1
35	1
36	1
37	1
38	5
39	1
40	1
41	1
42	1
43	1
44	1
45	1
46	1
47	3
48	1
49	1
50	1
51	1
52	1
53	7
54	1
55	1
56	1
57	1
58	1
59	1
60	1
61	1
62	1
63	1
64	1
65	43
66	1
67	19
68	9
69	1
70	1
71	1
72	1
73	1
74	1
75	1
76	1
77	3
78	5
79	1
80	1
81	23
82	1
83	11
84	1
85	1
86	1
87	1
88	1
89	1
90	1
91	1
92	1
93	1
94	1
95	3
96	1
97	1
98	13
99	1
100	1
101	1
102	1
103	1
104	1
105	1