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 A259265 #9 Jul 10 2015 00:32:52
%S A259265 5,5,31,346201,209102521,
%T A259265 6813584502670671709484968734757499815278649237224386797415881735111285309440001
%N A259265 Primes of the form Phi(5,n!), where Phi is the cyclotomic polynomial.
%C A259265 These primes are neither sorted nor uniqued. They are listed in the order found in A259264.
%H A259265 OEIS Wiki, <a href="https://oeis.org/wiki/Cyclotomic Polynomials at x=sigma(n)">Cyclotomic Polynomials at x=sigma(n)</a>
%t A259265 Select[Table[Cyclotomic[5, n!], {n, 0, 200}], PrimeQ]
%Y A259265 Cf. A200906.
%K A259265 nonn
%O A259265 1,1
%A A259265 _Robert Price_, Jun 22 2015