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 A090474 #9 Nov 17 2018 22:14:15
%S A090474 2,3,11,17,67,101,1609,1811,7243,43457,108643,488893,5214857,23466857,
%T A090474 938674273,3872031377,29040235327,542084392769,65659972074139,
%U A090474 3179324963589889,58420096205964211,1849969713188866681,76465414811806489481,1881049204370439641233,94052460218521982061649
%N A090474 Beginning with 2, a(n+1) is the least prime == 1 (mod (Sum_{i=1..n} a(i))).
%t A090474 s = t = 2; Print[t]; Do[k = 1; While[ !PrimeQ[k*t + 1], k++ ]; p = k*t + 1; Print[p]; t += p, {n, 2, 30}] (* _Ryan Propper_, Jul 29 2005 *)
%K A090474 nonn
%O A090474 1,1
%A A090474 _Amarnath Murthy_, Dec 02 2003
%E A090474 More terms from _Ryan Propper_, Jul 29 2005
%E A090474 Further terms from _David Wasserman_, Nov 16 2005