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.

A098221 a(n) is the smallest number x such that floor(sigma(sigma(x))/x) = n or the A098219(x) quotient equals n.

Table of values

n a(n)
1 1
2 2
3 8
4 6
5 40
6 30
7 24
8 60
9 120
10 480
11 540
12 1560
13 2520
14 10920
15 27720
16 30240
17 191520
18 524160
19 360360
20 3243240
21 5765760
22 28828800
23 109549440
24 438197760
25 766846080
26 3834230400
27 9081072000
28 32974381440
29 147516969600
30 880887047040
31 2802822422400

List of values

[1, 2, 8, 6, 40, 30, 24, 60, 120, 480, 540, 1560, 2520, 10920, 27720, 30240, 191520, 524160, 360360, 3243240, 5765760, 28828800, 109549440, 438197760, 766846080, 3834230400, 9081072000, 32974381440, 147516969600, 880887047040, 2802822422400]

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

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