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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.

A211876 Primes of the form Phi(phi(k),2), the phi(k)-th cyclotomic polynomial evaluated at 2, where phi is the Euler totient function.

Table of values

n a(n)
1 3
2 5
3 11
4 13
5 17
6 241
7 257
8 331
9 683
10 5419
11 61681
12 65537
13 2796203
14 15790321
15 22366891
16 4278255361
17 4562284561
18 77158673929
19 1133836730401
20 18446744069414584321
21 291280009243618888211558641
22 78919881726271091143763623681
23 84159375948762099254554456081
24 84179842077657862011867889681

List of values

[3, 5, 11, 13, 17, 241, 257, 331, 683, 5419, 61681, 65537, 2796203, 15790321, 22366891, 4278255361, 4562284561, 77158673929, 1133836730401, 18446744069414584321, 291280009243618888211558641, 78919881726271091143763623681, 84159375948762099254554456081, 84179842077657862011867889681]

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

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