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.

A081238 #{(i,j): mu(i)*mu(j) = -1, 1 <= i <= n, 1 <= j <= n}, where mu=A008683 (Moebius function).

Table of values

n a(n)
1 0
2 2
3 4
4 4
5 6
6 12
7 16
8 16
9 16
10 24
11 30
12 30
13 36
14 48
15 60
16 60
17 70
18 70
19 80
20 80
21 96
22 112
23 126
24 126
25 126
26 144
27 144
28 144
29 160
30 176
31 192
32 192
33 216
34 240
35 264
36 264
37 286
38 312
39 338
40 338
41 364
42 390
43 416
44 416
45 416
46 448
47 476
48 476
49 476
50 476
51 510
52 510
53 540
54 540
55 576
56 576
57 612
58 648

List of values

[0, 2, 4, 4, 6, 12, 16, 16, 16, 24, 30, 30, 36, 48, 60, 60, 70, 70, 80, 80, 96, 112, 126, 126, 126, 144, 144, 144, 160, 176, 192, 192, 216, 240, 264, 264, 286, 312, 338, 338, 364, 390, 416, 416, 416, 448, 476, 476, 476, 476, 510, 510, 540, 540, 576, 576, 612, 648]

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

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