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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.

A091531 Primes p such that k = 2p is the smallest positive solution to the equation phi(p+k) = phi(p) + phi(k), where phi is Euler's totient function.

Table of values

n a(n)
1 7
2 23
3 31
4 43
5 59
6 67
7 71
8 73
9 101
10 103
11 107
12 127
13 131
14 137
15 139
16 179
17 199
18 211
19 223
20 227
21 239
22 269
23 281
24 283
25 307
26 311
27 331
28 347
29 359
30 367
31 379
32 383
33 431
34 439
35 463
36 467
37 479
38 487
39 491
40 503
41 523
42 547
43 563
44 571
45 607
46 619
47 631
48 643
49 659
50 661
51 683
52 691
53 719
54 727

List of values

[7, 23, 31, 43, 59, 67, 71, 73, 101, 103, 107, 127, 131, 137, 139, 179, 199, 211, 223, 227, 239, 269, 281, 283, 307, 311, 331, 347, 359, 367, 379, 383, 431, 439, 463, 467, 479, 487, 491, 503, 523, 547, 563, 571, 607, 619, 631, 643, 659, 661, 683, 691, 719, 727]

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

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