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.

A099047 Numbers n such that n-1 and n+1 are both composite.

Table of values

n a(n)
1 5
2 7
3 9
4 11
5 13
6 15
7 17
8 19
9 21
10 23
11 25
12 26
13 27
14 29
15 31
16 33
17 34
18 35
19 37
20 39
21 41
22 43
23 45
24 47
25 49
26 50
27 51
28 53
29 55
30 56
31 57
32 59
33 61
34 63
35 64
36 65
37 67
38 69
39 71
40 73
41 75
42 76
43 77
44 79
45 81
46 83
47 85
48 86
49 87
50 89
51 91
52 92
53 93
54 94
55 95
56 97
57 99
58 101
59 103
60 105
61 107
62 109
63 111
64 113
65 115
66 116
67 117

List of values

[5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 26, 27, 29, 31, 33, 34, 35, 37, 39, 41, 43, 45, 47, 49, 50, 51, 53, 55, 56, 57, 59, 61, 63, 64, 65, 67, 69, 71, 73, 75, 76, 77, 79, 81, 83, 85, 86, 87, 89, 91, 92, 93, 94, 95, 97, 99, 101, 103, 105, 107, 109, 111, 113, 115, 116, 117]

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

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