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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.

A088830 a(n) = Min{x : sigma(x) = n*phi(x), x is not a prime}, the least nonprime solutions to sigma(x) = n*phi(x); special balanced numbers.

Table of values

n a(n)
1 1
2 35
3 15
4 14
5 56
6 6
7 12
8 42
9 30
10 168
11 2580
12 210
13 630
14 420
15 840
16 20790
17 416640
18 9240
19 291060
20 83160
21 120120
22 5165160
23 1719277560
24 43825320
25 26860680
26 277560360
27 1304863560
28 569729160
29 587133466920
30 16522145640
31 33044291280
32 563462139240
33 1140028049160

List of values

[1, 35, 15, 14, 56, 6, 12, 42, 30, 168, 2580, 210, 630, 420, 840, 20790, 416640, 9240, 291060, 83160, 120120, 5165160, 1719277560, 43825320, 26860680, 277560360, 1304863560, 569729160, 587133466920, 16522145640, 33044291280, 563462139240, 1140028049160]

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

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