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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.

A140173 Numbers k such that sigma(k) = phi(k)*(sum of the digits of k).

Table of values

n a(n)
1 1
2 6
3 3720
4 25080
5 237000
6 353430
7 1201560
8 1402440
9 2104440
10 2147040
11 4140360
12 22007160
13 60035220
14 104370420
15 110095020
16 136222020
17 402500280
18 2203551000
19 2223003120
20 8720021310
21 35590401000
22 110232105060
23 116046010080
24 212062116000
25 440401221000
26 2181301242120

List of values

[1, 6, 3720, 25080, 237000, 353430, 1201560, 1402440, 2104440, 2147040, 4140360, 22007160, 60035220, 104370420, 110095020, 136222020, 402500280, 2203551000, 2223003120, 8720021310, 35590401000, 110232105060, 116046010080, 212062116000, 440401221000, 2181301242120]

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

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