A103960 - cp's OEIS frontend

A103960 Number of primes p such that prime(n)*p - 2 is prime and p <= prime(n).

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

[1, 1, 2, 2, 2, 3, 1, 2, 4, 3, 2, 5, 3, 3, 5, 3, 4, 4, 4, 5, 6, 3, 4, 6, 3, 5, 6, 5, 3, 6, 5, 8, 5, 5, 6, 5, 7, 9, 7, 6, 6, 5, 7, 6, 8, 5, 8, 10, 5, 6, 8, 6, 7, 7, 10, 10, 3, 11, 8, 11, 6, 10, 8, 12, 9, 9, 7, 11, 9, 7, 8, 9, 6, 14, 8, 10, 11, 11, 12, 11, 7, 8]

cp's OEIS Frontend

A103960 Number of primes p such that prime(n)*p - 2 is prime and p <= prime(n).

Table of values

List of values

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

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

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