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.

A172458 Nonprimes n such that exactly one of 2n-1 and 2n+1 is prime.

Table of values

n a(n)
1 1
2 4
3 8
4 10
5 12
6 14
7 16
8 18
9 20
10 22
11 24
12 26
13 27
14 33
15 34
16 35
17 39
18 40
19 42
20 44
21 45
22 48
23 49
24 50
25 52
26 55
27 56
28 57
29 63
30 64
31 65
32 66
33 68
34 70
35 74
36 76
37 78
38 81
39 82
40 84
41 86
42 87
43 91
44 95
45 98
46 100
47 105
48 106
49 111
50 112
51 115
52 116
53 117
54 119
55 121
56 125
57 126
58 128
59 129
60 132
61 134
62 136
63 138
64 140

List of values

[1, 4, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 27, 33, 34, 35, 39, 40, 42, 44, 45, 48, 49, 50, 52, 55, 56, 57, 63, 64, 65, 66, 68, 70, 74, 76, 78, 81, 82, 84, 86, 87, 91, 95, 98, 100, 105, 106, 111, 112, 115, 116, 117, 119, 121, 125, 126, 128, 129, 132, 134, 136, 138, 140]

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

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