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.

A001229 Numbers k such that phi(sigma(k)) = k.

Table of values

n a(n)
1 1
2 2
3 8
4 12
5 128
6 240
7 720
8 6912
9 32768
10 142560
11 712800
12 1140480
13 1190400
14 3345408
15 3571200
16 5702400
17 14859936
18 29719872
19 50319360
20 118879488
21 2147483648
22 3889036800
23 4389396480
24 21946982400
25 47416320000
26 92177326080
27 133145026560
28 331914240000
29 460886630400
30 665725132800

List of values

[1, 2, 8, 12, 128, 240, 720, 6912, 32768, 142560, 712800, 1140480, 1190400, 3345408, 3571200, 5702400, 14859936, 29719872, 50319360, 118879488, 2147483648, 3889036800, 4389396480, 21946982400, 47416320000, 92177326080, 133145026560, 331914240000, 460886630400, 665725132800]

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

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