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.

A189764 Greatest integer x such that x' = 2n and x is not a semiprime, or 0 if there is no such x, where x' is the arithmetic derivative (A003415).

Table of values

n a(n)
1 0
2 0
3 0
4 0
5 0
6 8
7 0
8 12
9 0
10 0
11 0
12 20
13 0
14 0
15 0
16 28
17 0
18 0
19 0
20 0
21 0
22 24
23 0
24 44
25 0
26 0
27 0
28 52
29 0
30 36
31 0
32 0
33 0
34 40
35 0
36 68
37 0
38 0
39 0
40 76
41 0
42 0
43 0
44 0
45 0
46 60
47 0
48 92
49 0
50 0
51 0
52 0
53 0
54 81
55 0
56 48
57 0
58 0
59 0
60 116
61 0
62 84
63 0
64 124
65 0
66 0
67 0
68 0
69 0
70 100
71 0
72 0
73 0
74 0
75 0
76 148
77 0
78 72

List of values

[0, 0, 0, 0, 0, 8, 0, 12, 0, 0, 0, 20, 0, 0, 0, 28, 0, 0, 0, 0, 0, 24, 0, 44, 0, 0, 0, 52, 0, 36, 0, 0, 0, 40, 0, 68, 0, 0, 0, 76, 0, 0, 0, 0, 0, 60, 0, 92, 0, 0, 0, 0, 0, 81, 0, 48, 0, 0, 0, 116, 0, 84, 0, 124, 0, 0, 0, 0, 0, 100, 0, 0, 0, 0, 0, 148, 0, 72]

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

Content is available under The OEIS End-User License Agreement.