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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.

A228519 Numbers n such that sigma(n) = sigma(n - phi(n)), where sigma(n) is the sum of divisors of n and phi(n) is the Euler totient function of n.

Table of values

n a(n)
1 9356
2 52412
3 110442
4 160834
5 220884
6 266866
7 289230
8 321668
9 420790
10 441768
11 533732
12 556818
13 578460
14 643336
15 731530
16 841580
17 883536
18 1067464
19 1113636
20 1156920
21 1286672
22 1446150
23 1463060
24 1683160
25 1767072
26 2103950
27 2134928
28 2227272
29 2313840
30 2545888
31 2573344
32 2892300

List of values

[9356, 52412, 110442, 160834, 220884, 266866, 289230, 321668, 420790, 441768, 533732, 556818, 578460, 643336, 731530, 841580, 883536, 1067464, 1113636, 1156920, 1286672, 1446150, 1463060, 1683160, 1767072, 2103950, 2134928, 2227272, 2313840, 2545888, 2573344, 2892300]

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

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