A305983 - cp's OEIS frontend

A305983 Filter sequence combining from all proper divisors d of n, the prime signature of 2d+1.

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

[1, 2, 2, 3, 2, 4, 2, 5, 3, 4, 2, 6, 2, 7, 4, 8, 2, 9, 2, 10, 7, 4, 2, 11, 3, 12, 4, 10, 2, 13, 2, 10, 4, 7, 7, 14, 2, 7, 12, 15, 2, 13, 2, 16, 9, 4, 2, 17, 18, 19, 7, 20, 2, 13, 4, 21, 7, 4, 2, 22, 2, 23, 24, 25, 12, 26, 2, 27, 4, 28, 2, 29, 2, 23, 24, 27, 7, 30, 2, 31, 32, 4, 2, 33, 7, 7, 4, 34, 2, 35, 36, 10, 23, 7, 7, 37, 2, 38, 9, 39, 2, 28, 2, 40, 13]

cp's OEIS Frontend

A305983 Filter sequence combining from all proper divisors d of n, the prime signature of 2d+1.

Table of values

List of values

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

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

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