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.

A015623 Quadruples of different integers from [ 1,n ] with no common factors between pairs.

Table of values

n a(n)
1 0
2 0
3 0
4 0
5 2
6 2
7 10
8 14
9 24
10 26
11 68
12 72
13 151
14 167
15 192
16 228
17 411
18 431
19 708
20 758
21 858
22 928
23 1419
24 1475
25 1874
26 2013
27 2353
28 2499
29 3515
30 3571
31 4856
32 5254
33 5747
34 6089
35 6795
36 6979
37 9129
38 9630
39 10437
40 10800
41 13768
42 13978
43 17500
44 18275
45 19210
46 20114
47 24734

List of values

[0, 0, 0, 0, 2, 2, 10, 14, 24, 26, 68, 72, 151, 167, 192, 228, 411, 431, 708, 758, 858, 928, 1419, 1475, 1874, 2013, 2353, 2499, 3515, 3571, 4856, 5254, 5747, 6089, 6795, 6979, 9129, 9630, 10437, 10800, 13768, 13978, 17500, 18275, 19210, 20114, 24734]

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

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