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.

A352749 a(n) = pi(n) * (pi(2n-1) - pi(n-1)).

Table of values

n a(n)
1 0
2 2
3 4
4 4
5 6
6 6
7 12
8 8
9 12
10 16
11 20
12 20
13 24
14 18
15 24
16 30
17 35
18 28
19 40
20 32
21 40
22 48
23 54
24 54
25 54
26 54
27 63
28 63
29 70
30 70
31 88
32 77
33 77
34 88
35 88
36 99
37 120
38 108
39 108
40 120
41 130
42 130
43 140
44 126
45 140
46 140
47 150
48 135
49 150
50 150
51 165
52 180
53 192
54 192
55 208
56 208
57 224
58 224
59 238
60 221
61 234
62 216
63 216
64 234

List of values

[0, 2, 4, 4, 6, 6, 12, 8, 12, 16, 20, 20, 24, 18, 24, 30, 35, 28, 40, 32, 40, 48, 54, 54, 54, 54, 63, 63, 70, 70, 88, 77, 77, 88, 88, 99, 120, 108, 108, 120, 130, 130, 140, 126, 140, 140, 150, 135, 150, 150, 165, 180, 192, 192, 208, 208, 224, 224, 238, 221, 234, 216, 216, 234]

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

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