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 A062698 #20 Apr 16 2025 19:41:30
%S A062698 3,5,13,241,958003201,12804747411456001,
%T A062698 20666295932772289859333302675046400000001,
%U A062698 3102237506574764560448486032938606422126519440033972224000000000001,8549766568120051128596027506778799299380687576733627449344000000000001
%N A062698 Primes of form 2*k! + 1.
%H A062698 Harry J. Smith, <a href="/A062698/b062698.txt">Table of n, a(n) for n=1,...,12</a>
%F A062698 a(n) = A052898(A051915(n+1)). - _Elmo R. Oliveira_, Apr 16 2025
%t A062698 lst={};Do[p=2*n!+1;If[PrimeQ[p],AppendTo[lst,p]],{n,0,5!}];lst (* _Vladimir Joseph Stephan Orlovsky_, Jan 28 2009 *)
%t A062698 Select[2*Range[200]!+1,PrimeQ] (* _Harvey P. Dale_, Oct 26 2013 *)
%o A062698 (PARI) for(n=1,55, if(isprime(2*n!+1),print(2*n!+1)))
%o A062698 (PARI) { n=0; f=1; for (m=1, 10^5, f*=m; if(isprime(a=2*f + 1), write("b062698.txt", n++, " ", a); if (n==12, break)) ) } \\ _Harry J. Smith_, Aug 09 2009
%Y A062698 Cf. A051915, A052898.
%K A062698 nonn
%O A062698 1,1
%A A062698 _Jason Earls_, Jul 10 2001
%E A062698 One additional term from _Harvey P. Dale_, Oct 26 2013