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A256241 Numbers n whose Euler's totient function phi(n), divided by two, plus one, p = (phi(n) / 2) + 1, is a divisor of n.

Table of values

n a(n)
1 4
2 6
3 12
4 15
5 20
6 21
7 28
8 30
9 33
10 39
11 42
12 44
13 51
14 52
15 57
16 66
17 68
18 69
19 76
20 78
21 87
22 92
23 93
24 102
25 111
26 114
27 116
28 123
29 124
30 129
31 138
32 141
33 148
34 159
35 164
36 172
37 174
38 177
39 183
40 186
41 188
42 201
43 212
44 213
45 219
46 222
47 236
48 237
49 244
50 246
51 249
52 258
53 267
54 268
55 282
56 284
57 291
58 292
59 303
60 309
61 316
62 318
63 321
64 327
65 332
66 339
67 354
68 356
69 366

List of values

[4, 6, 12, 15, 20, 21, 28, 30, 33, 39, 42, 44, 51, 52, 57, 66, 68, 69, 76, 78, 87, 92, 93, 102, 111, 114, 116, 123, 124, 129, 138, 141, 148, 159, 164, 172, 174, 177, 183, 186, 188, 201, 212, 213, 219, 222, 236, 237, 244, 246, 249, 258, 267, 268, 282, 284, 291, 292, 303, 309, 316, 318, 321, 327, 332, 339, 354, 356, 366]