cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A075084 Number of composite numbers c with n <= c <= 2*n.

Table of values

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

List of values

[0, 1, 2, 3, 4, 5, 5, 7, 7, 7, 8, 9, 10, 12, 12, 12, 13, 15, 15, 17, 17, 17, 18, 19, 20, 21, 21, 22, 23, 24, 24, 26, 27, 27, 28, 28, 28, 30, 31, 31, 32, 33, 34, 36, 36, 37, 38, 40, 40, 41, 41, 41, 42, 43, 43, 44, 44, 45, 46, 48, 49, 51, 52, 52, 53, 53, 54, 56, 56, 56, 57, 59, 60]

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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