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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.

A225774 Primes p such that sigma(sigma(p)) = 2*phi(p); sigma(n) = A000203(n); phi(n) = A000010(n).

Table of values

n a(n)
1 13
2 43
3 109
4 151
5 883
6 2143
7 34360131583

List of values

[13, 43, 109, 151, 883, 2143, 34360131583]

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