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 A068948 #8 Jun 27 2018 09:33:00 %S A068948 2,3,7,13,17,43,83,167,313,1667,6833,8167,191833,298327,3143167, %T A068948 197222917,994927133,3160522105583 %N A068948 Primes in A068947. %C A068948 a(19) > 10^13. - _Giovanni Resta_, Jun 27 2018 %e A068948 a(4)=13 since 13 is the fourth prime in A068947. %Y A068948 Cf. A068809, A068947. %K A068948 more,nonn,base %O A068948 1,1 %A A068948 Francois Jooste (phukraut(AT)hotmail.com), Mar 15 2002 %E A068948 a(16)-a(17) from _Sean A. Irvine_, Jun 07 2011 %E A068948 a(18) from _Giovanni Resta_, Jun 27 2018