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.

A368042 Moduli k for which the number of quadratic residues mod k coprime to k is phi(k)/2^r for positive r = (phi(k)/lambda(k)) - x, x > 0, where lambda is Carmichael's function. Complement of A366935.

Table of values

n a(n)
1 2
2 24
3 40
4 48
5 56
6 60
7 63
8 65
9 72
10 80
11 84
12 85
13 88
14 91
15 96
16 104
17 105
18 112
19 117
20 120
21 126
22 130
23 132
24 133
25 136
26 140
27 144
28 145
29 152
30 156
31 160
32 165
33 168
34 170
35 171
36 176
37 180
38 182
39 184
40 185
41 189
42 192
43 195
44 200
45 204
46 205
47 208
48 210
49 216
50 217

List of values

[2, 24, 40, 48, 56, 60, 63, 65, 72, 80, 84, 85, 88, 91, 96, 104, 105, 112, 117, 120, 126, 130, 132, 133, 136, 140, 144, 145, 152, 156, 160, 165, 168, 170, 171, 176, 180, 182, 184, 185, 189, 192, 195, 200, 204, 205, 208, 210, 216, 217]

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

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