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.

A380315 Denominator of sum of reciprocals of all prime divisors of all positive integers <= n.

Table of values

n a(n)
1 1
2 2
3 6
4 3
5 15
6 30
7 210
8 105
9 35
10 70
11 770
12 1155
13 15015
14 30030
15 30030
16 15015
17 255255
18 170170
19 3233230
20 1616615
21 4849845
22 9699690
23 223092870
24 111546435
25 22309287
26 44618574
27 14872858
28 7436429
29 215656441
30 6469693230
31 200560490130
32 100280245065
33 100280245065

List of values

[1, 2, 6, 3, 15, 30, 210, 105, 35, 70, 770, 1155, 15015, 30030, 30030, 15015, 255255, 170170, 3233230, 1616615, 4849845, 9699690, 223092870, 111546435, 22309287, 44618574, 14872858, 7436429, 215656441, 6469693230, 200560490130, 100280245065, 100280245065]

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

Content is available under The OEIS End-User License Agreement.