A087724 - cp's OEIS frontend

A087724 a(n) = -PrimePi(n) +floor( prime(n)/log(n))-2.

n	a(n)
2	1
3	0
4	1
5	1
6	2
7	2
8	3
9	4
10	6
11	5
12	7
13	7
14	8
15	9
16	11
17	11
18	12
19	12
20	13
21	13
22	15
23	15
24	17
25	19
26	19
27	20
28	21
29	20
30	21
31	23
32	24
33	26
34	26
35	28
36	29
37	29
38	30
39	31
40	32
41	33
42	33
43	34
44	35
45	35
46	35
47	37
48	40
49	41
50	41
51	42
52	43
53	42
54	44
55	46
56	47
57	48
58	48
59	48
60	49
61	48
62	50
63	54
64	54
65	54
66	55
67	57
68	58
69	60
70	61
71	60
72	61
73	62
74	63
75	64

[1, 0, 1, 1, 2, 2, 3, 4, 6, 5, 7, 7, 8, 9, 11, 11, 12, 12, 13, 13, 15, 15, 17, 19, 19, 20, 21, 20, 21, 23, 24, 26, 26, 28, 29, 29, 30, 31, 32, 33, 33, 34, 35, 35, 35, 37, 40, 41, 41, 42, 43, 42, 44, 46, 47, 48, 48, 48, 49, 48, 50, 54, 54, 54, 55, 57, 58, 60, 61, 60, 61, 62, 63, 64]

cp's OEIS Frontend

A087724 a(n) = -PrimePi(n) +floor( prime(n)/log(n))-2.

Table of values

List of values

n	a(n)
2	1
3	0
4	1
5	1
6	2
7	2
8	3
9	4
10	6
11	5
12	7
13	7
14	8
15	9
16	11
17	11
18	12
19	12
20	13
21	13
22	15
23	15
24	17
25	19
26	19
27	20
28	21
29	20
30	21
31	23
32	24
33	26
34	26
35	28
36	29
37	29
38	30
39	31
40	32
41	33
42	33
43	34
44	35
45	35
46	35
47	37
48	40
49	41
50	41
51	42
52	43
53	42
54	44
55	46
56	47
57	48
58	48
59	48
60	49
61	48
62	50
63	54
64	54
65	54
66	55
67	57
68	58
69	60
70	61
71	60
72	61
73	62
74	63
75	64

n	a(n)
2	1
3	0
4	1
5	1
6	2
7	2
8	3
9	4
10	6
11	5
12	7
13	7
14	8
15	9
16	11
17	11
18	12
19	12
20	13
21	13
22	15
23	15
24	17
25	19
26	19
27	20
28	21
29	20
30	21
31	23
32	24
33	26
34	26
35	28
36	29
37	29
38	30
39	31
40	32
41	33
42	33
43	34
44	35
45	35
46	35
47	37
48	40
49	41
50	41
51	42
52	43
53	42
54	44
55	46
56	47
57	48
58	48
59	48
60	49
61	48
62	50
63	54
64	54
65	54
66	55
67	57
68	58
69	60
70	61
71	60
72	61
73	62
74	63
75	64

n	a(n)
2	1
3	0
4	1
5	1
6	2
7	2
8	3
9	4
10	6
11	5
12	7
13	7
14	8
15	9
16	11
17	11
18	12
19	12
20	13
21	13
22	15
23	15
24	17
25	19
26	19
27	20
28	21
29	20
30	21
31	23
32	24
33	26
34	26
35	28
36	29
37	29
38	30
39	31
40	32
41	33
42	33
43	34
44	35
45	35
46	35
47	37
48	40
49	41
50	41
51	42
52	43
53	42
54	44
55	46
56	47
57	48
58	48
59	48
60	49
61	48
62	50
63	54
64	54
65	54
66	55
67	57
68	58
69	60
70	61
71	60
72	61
73	62
74	63
75	64