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.

A076271 a(1) = 1, a(2) = 2, and for n > 2, a(n) = a(n-1) + gpf(a(n-1)), where gpf = greatest prime factor = A006530.

Table of values

n a(n)
1 1
2 2
3 4
4 6
5 9
6 12
7 15
8 20
9 25
10 30
11 35
12 42
13 49
14 56
15 63
16 70
17 77
18 88
19 99
20 110
21 121
22 132
23 143
24 156
25 169
26 182
27 195
28 208
29 221
30 238
31 255
32 272
33 289
34 306
35 323
36 342
37 361
38 380
39 399
40 418
41 437
42 460
43 483
44 506
45 529
46 552
47 575
48 598
49 621
50 644
51 667
52 696
53 725
54 754
55 783
56 812
57 841

List of values

[1, 2, 4, 6, 9, 12, 15, 20, 25, 30, 35, 42, 49, 56, 63, 70, 77, 88, 99, 110, 121, 132, 143, 156, 169, 182, 195, 208, 221, 238, 255, 272, 289, 306, 323, 342, 361, 380, 399, 418, 437, 460, 483, 506, 529, 552, 575, 598, 621, 644, 667, 696, 725, 754, 783, 812, 841]

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

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