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.
%I A292009 #8 Nov 11 2019 13:51:51
%S A292009 31,19531,521,12207031,601,305175781,390001,234750601,
%T A292009 177635683940025046467781066894531,152587500001,
%U A292009 227376585863531112677002031251,59509429687890001,11735415506748076408140121,9080418348371887359375390001,60081451169922001
%N A292009 Primes of the form Phi(k, 5), where Phi is the cyclotomic polynomial.
%H A292009 Robert Price, <a href="/A292009/b292009.txt">Table of n, a(n) for n = 1..32</a>
%H A292009 Yves Gallot, <a href="http://yves.gallot.pagesperso-orange.fr/papers/cyclotomic.html">Cyclotomic polynomials and prime numbers</a>
%H A292009 <a href="/index/Cy#CyclotomicPolynomialsValuesAtX">Index entries for cyclotomic polynomials,values at X</a>
%t A292009 Select[Table[Cyclotomic[k,5], {k, 0, 100}], PrimeQ[#] &]
%Y A292009 Cf. A138935.
%K A292009 nonn
%O A292009 1,1
%A A292009 _Robert Price_, Sep 07 2017