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 A087609 #5 Dec 05 2013 19:56:32 %S A087609 13,113,0,11113,444443,0,22222223,111111113,0,11111111113, %T A087609 444444444443,0,373737373737373737373737373,777777777777773,0, %U A087609 171717171717171717171717171717173,1491491491491491491491491491491491491491491491491493,0,1851851851851851851851851851851851851851851851851851851853 %N A087609 Primes arising in A087604, or 0 if A087604(n) = 0. %C A087609 Either a(13)=0 or a(13) > 363636363636363636363636363. - _Sam Alexander_, Oct 20 2003 %Y A087609 Cf. A086920, A087604, A087605, A087606, A087607, A087608, A087610. %K A087609 base,nonn %O A087609 1,1 %A A087609 _Amarnath Murthy_, Sep 18 2003 %E A087609 More terms from _Sam Alexander_, Oct 20 2003 %E A087609 More terms from _David Wasserman_, Jun 16 2005