A064661 - cp's OEIS frontend

A064661 a(n) = n - floor( prime(n)/log(prime(n)) ).

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

[-1, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 4, 5, 5, 4, 5, 5, 6, 6, 7, 5, 6, 6, 6, 6, 6, 6, 7, 7, 7, 7, 8, 7, 8, 8, 9, 8, 7, 8, 8, 9, 9, 10, 9, 9, 9, 9, 10, 10, 11, 11, 11, 10, 10, 11, 11, 10, 11, 10, 11, 11, 11, 11, 12, 12, 12, 12, 12, 13, 12, 12]

cp's OEIS Frontend

A064661 a(n) = n - floor( prime(n)/log(prime(n)) ).

Table of values

List of values

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

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

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