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 A135562 #4 Mar 30 2012 17:34:57
%S A135562 19,829,9439,99139,983449,9973219,99982249,999986179,9999857299,
%T A135562 99999895609,999999843259,9999999990529,99999999950449,
%U A135562 999999999984529,9999999999854539,99999999998034559,999999999999371719
%N A135562 Last member of largest n-digit prime quadruplet.
%e A135562 a(4) = 9439 because the largest 4-digit prime quadruplet is {9431, 9433, 9437, 9439}.
%Y A135562 Cf. A120120.
%K A135562 base,nonn
%O A135562 2,1
%A A135562 Julien Peter Benney (jpbenney(AT)gmail.com), Feb 23 2008
%E A135562 Offset corrected and a(8)-a(18) from _Donovan Johnson_, May 23 2010