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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.

A180643 Numbers n such that 1+phi(n)^2 is prime. Phi is the Euler totient function.

Table of values

n a(n)
1 1
2 2
3 3
4 4
5 5
6 6
7 7
8 8
9 9
10 10
11 11
12 12
13 14
14 17
15 18
16 22
17 25
18 32
19 33
20 34
21 35
22 37
23 39
24 40
25 41
26 44
27 45
28 48
29 50
30 52
31 55
32 56
33 57
34 60
35 63
36 66
37 67
38 70
39 72
40 74
41 75
42 76
43 78
44 81
45 82
46 84
47 87
48 88
49 90
50 100
51 108
52 110
53 114
54 116
55 121
56 126
57 127
58 129
59 131
60 132
61 134
62 143
63 147
64 150
65 151
66 155

List of values

[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 17, 18, 22, 25, 32, 33, 34, 35, 37, 39, 40, 41, 44, 45, 48, 50, 52, 55, 56, 57, 60, 63, 66, 67, 70, 72, 74, 75, 76, 78, 81, 82, 84, 87, 88, 90, 100, 108, 110, 114, 116, 121, 126, 127, 129, 131, 132, 134, 143, 147, 150, 151, 155]

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

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