A156874 - cp's OEIS frontend

A156874 Number of Sophie Germain primes <= n.

n	a(n)
1	0
2	1
3	2
4	2
5	3
6	3
7	3
8	3
9	3
10	3
11	4
12	4
13	4
14	4
15	4
16	4
17	4
18	4
19	4
20	4
21	4
22	4
23	5
24	5
25	5
26	5
27	5
28	5
29	6
30	6
31	6
32	6
33	6
34	6
35	6
36	6
37	6
38	6
39	6
40	6
41	7
42	7
43	7
44	7
45	7
46	7
47	7
48	7
49	7
50	7
51	7
52	7
53	8
54	8
55	8
56	8
57	8
58	8
59	8
60	8
61	8
62	8
63	8
64	8
65	8
66	8
67	8
68	8
69	8
70	8
71	8
72	8
73	8
74	8
75	8
76	8
77	8
78	8
79	8
80	8
81	8
82	8
83	9
84	9
85	9
86	9
87	9
88	9
89	10
90	10
91	10
92	10
93	10
94	10
95	10
96	10
97	10
98	10
99	10

[0, 1, 2, 2, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 9, 9, 9, 9, 9, 9, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10]

cp's OEIS Frontend

A156874 Number of Sophie Germain primes <= n.

Table of values

List of values

n	a(n)
1	0
2	1
3	2
4	2
5	3
6	3
7	3
8	3
9	3
10	3
11	4
12	4
13	4
14	4
15	4
16	4
17	4
18	4
19	4
20	4
21	4
22	4
23	5
24	5
25	5
26	5
27	5
28	5
29	6
30	6
31	6
32	6
33	6
34	6
35	6
36	6
37	6
38	6
39	6
40	6
41	7
42	7
43	7
44	7
45	7
46	7
47	7
48	7
49	7
50	7
51	7
52	7
53	8
54	8
55	8
56	8
57	8
58	8
59	8
60	8
61	8
62	8
63	8
64	8
65	8
66	8
67	8
68	8
69	8
70	8
71	8
72	8
73	8
74	8
75	8
76	8
77	8
78	8
79	8
80	8
81	8
82	8
83	9
84	9
85	9
86	9
87	9
88	9
89	10
90	10
91	10
92	10
93	10
94	10
95	10
96	10
97	10
98	10
99	10

n	a(n)
1	0
2	1
3	2
4	2
5	3
6	3
7	3
8	3
9	3
10	3
11	4
12	4
13	4
14	4
15	4
16	4
17	4
18	4
19	4
20	4
21	4
22	4
23	5
24	5
25	5
26	5
27	5
28	5
29	6
30	6
31	6
32	6
33	6
34	6
35	6
36	6
37	6
38	6
39	6
40	6
41	7
42	7
43	7
44	7
45	7
46	7
47	7
48	7
49	7
50	7
51	7
52	7
53	8
54	8
55	8
56	8
57	8
58	8
59	8
60	8
61	8
62	8
63	8
64	8
65	8
66	8
67	8
68	8
69	8
70	8
71	8
72	8
73	8
74	8
75	8
76	8
77	8
78	8
79	8
80	8
81	8
82	8
83	9
84	9
85	9
86	9
87	9
88	9
89	10
90	10
91	10
92	10
93	10
94	10
95	10
96	10
97	10
98	10
99	10

n	a(n)
1	0
2	1
3	2
4	2
5	3
6	3
7	3
8	3
9	3
10	3
11	4
12	4
13	4
14	4
15	4
16	4
17	4
18	4
19	4
20	4
21	4
22	4
23	5
24	5
25	5
26	5
27	5
28	5
29	6
30	6
31	6
32	6
33	6
34	6
35	6
36	6
37	6
38	6
39	6
40	6
41	7
42	7
43	7
44	7
45	7
46	7
47	7
48	7
49	7
50	7
51	7
52	7
53	8
54	8
55	8
56	8
57	8
58	8
59	8
60	8
61	8
62	8
63	8
64	8
65	8
66	8
67	8
68	8
69	8
70	8
71	8
72	8
73	8
74	8
75	8
76	8
77	8
78	8
79	8
80	8
81	8
82	8
83	9
84	9
85	9
86	9
87	9
88	9
89	10
90	10
91	10
92	10
93	10
94	10
95	10
96	10
97	10
98	10
99	10