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.

A113609 Number of prime powers q<=n such that also q+2 is a prime power.

Table of values

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

List of values

[1, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 13, 13, 13, 13, 13, 13, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 16, 16, 16, 16, 16, 16, 16]

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

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