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.

A289835 Number of units u in Z/(2n-1)Z such that Phi(4,u) is a unit, where Phi is the cyclotomic polynomial.

Table of values

n a(n)
1 1
2 2
3 2
4 6
5 6
6 10
7 10
8 4
9 14
10 18
11 12
12 22
13 10
14 18
15 26
16 30
17 20
18 12
19 34
20 20
21 38
22 42
23 12
24 46
25 42
26 28
27 50
28 20
29 36
30 58
31 58
32 36
33 20
34 66
35 44
36 70
37 70
38 20
39 60
40 78
41 54
42 82
43 28
44 52
45 86
46 60
47 60
48 36
49 94
50 60
51 98
52 102
53 24
54 106
55 106
56 68
57 110
58 44
59 60
60 84
61 110
62 76
63 50
64 126
65 84

List of values

[1, 2, 2, 6, 6, 10, 10, 4, 14, 18, 12, 22, 10, 18, 26, 30, 20, 12, 34, 20, 38, 42, 12, 46, 42, 28, 50, 20, 36, 58, 58, 36, 20, 66, 44, 70, 70, 20, 60, 78, 54, 82, 28, 52, 86, 60, 60, 36, 94, 60, 98, 102, 24, 106, 106, 68, 110, 44, 60, 84, 110, 76, 50, 126, 84]

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

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