A079715 - cp's OEIS frontend

A079715 a(n) = pi(n) - pi(sqrt(n)) + 1.

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

[1, 2, 3, 2, 3, 3, 4, 4, 3, 3, 4, 4, 5, 5, 5, 5, 6, 6, 7, 7, 7, 7, 8, 8, 7, 7, 7, 7, 8, 8, 9, 9, 9, 9, 9, 9, 10, 10, 10, 10, 11, 11, 12, 12, 12, 12, 13, 13, 12, 12, 12, 12, 13, 13, 13, 13, 13, 13, 14, 14, 15, 15, 15, 15, 15, 15, 16, 16, 16, 16, 17, 17, 18, 18, 18, 18, 18, 18, 19, 19, 19, 19]

cp's OEIS Frontend

A079715 a(n) = pi(n) - pi(sqrt(n)) + 1.

Table of values

List of values

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

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

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