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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.

A137815 Year numbers: numbers n such that phi(n) = 2 phi(sigma(n)).

Table of values

n a(n)
1 5
2 13
3 37
4 61
5 65
6 73
7 119
8 157
9 185
10 193
11 277
12 305
13 313
14 365
15 397
16 421
17 457
18 481
19 541
20 613
21 661
22 673
23 733
24 757
25 785
26 793
27 877
28 949
29 965
30 997
31 1093
32 1153
33 1201
34 1213
35 1237
36 1321
37 1381
38 1385
39 1453
40 1547
41 1565
42 1615
43 1621
44 1657
45 1753
46 1873
47 1933
48 1985
49 1993

List of values

[5, 13, 37, 61, 65, 73, 119, 157, 185, 193, 277, 305, 313, 365, 397, 421, 457, 481, 541, 613, 661, 673, 733, 757, 785, 793, 877, 949, 965, 997, 1093, 1153, 1201, 1213, 1237, 1321, 1381, 1385, 1453, 1547, 1565, 1615, 1621, 1657, 1753, 1873, 1933, 1985, 1993]

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

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