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 A177514 #4 Mar 31 2012 10:26:16 %S A177514 73,733,7757,77557,777373,7777573,77757553,777777373,7777777237, %T A177514 77777773537,777777777773,7777777777573,77777777772257, %U A177514 777777777752557,7777777777752757,77777777777753233,777777777777753553 %N A177514 Largest n-digit emirp with only prime digits. %Y A177514 Cf. A177514, A128388 %K A177514 nonn,base %O A177514 2,1 %A A177514 _Lekraj Beedassy_, May 10 2010 %E A177514 a(8) and a(9) corrected and a(11)-a(18) from _Donovan Johnson_, Jul 30 2010