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.

A015616 Number of triples (i,j,k) with 1 <= i < j < k <= n and gcd(i,j,k) = 1.

Table of values

n a(n)
1 0
2 0
3 1
4 4
5 10
6 19
7 34
8 52
9 79
10 109
11 154
12 196
13 262
14 325
15 409
16 493
17 613
18 712
19 865
20 997
21 1171
22 1336
23 1567
24 1747
25 2017
26 2251
27 2548
28 2818
29 3196
30 3472
31 3907
32 4267
33 4717
34 5125
35 5665
36 6079
37 6709
38 7222
39 7858
40 8410
41 9190
42 9748
43 10609
44 11299
45 12127

List of values

[0, 0, 1, 4, 10, 19, 34, 52, 79, 109, 154, 196, 262, 325, 409, 493, 613, 712, 865, 997, 1171, 1336, 1567, 1747, 2017, 2251, 2548, 2818, 3196, 3472, 3907, 4267, 4717, 5125, 5665, 6079, 6709, 7222, 7858, 8410, 9190, 9748, 10609, 11299, 12127]

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

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