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.

A365677 Number of increasing geometric progressions in {1,2,3,...,n} with rational ratio and length >= 3.

Table of values

n a(n)
1 0
2 0
3 0
4 1
5 1
6 1
7 1
8 3
9 5
10 5
11 5
12 6
13 6
14 6
15 6
16 11
17 11
18 13
19 13
20 14
21 14
22 14
23 14
24 16
25 20
26 20
27 24
28 25
29 25
30 25
31 25
32 31
33 31
34 31
35 31
36 36
37 36
38 36
39 36
40 38
41 38
42 38
43 38
44 39
45 41
46 41
47 41
48 46
49 52
50 56
51 56
52 57
53 57
54 61
55 61
56 63
57 63
58 63
59 63
60 64
61 64
62 64
63 66
64 79
65 79
66 79
67 79
68 80
69 80
70 80
71 80
72 86
73 86
74 86
75 90
76 91
77 91

List of values

[0, 0, 0, 1, 1, 1, 1, 3, 5, 5, 5, 6, 6, 6, 6, 11, 11, 13, 13, 14, 14, 14, 14, 16, 20, 20, 24, 25, 25, 25, 25, 31, 31, 31, 31, 36, 36, 36, 36, 38, 38, 38, 38, 39, 41, 41, 41, 46, 52, 56, 56, 57, 57, 61, 61, 63, 63, 63, 63, 64, 64, 64, 66, 79, 79, 79, 79, 80, 80, 80, 80, 86, 86, 86, 90, 91, 91]

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

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