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 A176173 #2 Mar 31 2012 12:38:35
%S A176173 7,11,13,11,17,13,19,23,17,11,19,13,29,13,31,23,37,17,11,17,29,41,19,
%T A176173 43,31,17,19,13,47,13,19,23,37,53,23,41,59,17,23,43,61,17,29,19,47,19,
%U A176173 13,67,29,31,19,71,13,31,73,17,53,29,23,79,23,31,37,19,59,83,23,61,37,17
%N A176173 4th|largest prime-factor of n-th product of 4 distinct primes.
%C A176173 FactorInteger[210]=2*3*5*7,...
%t A176173 f0[n_]:=Last/@FactorInteger[n]=={1,1,1,1};f1[n_]:=Min[First/@FactorInteger[n]];f2[n_]:=First/@FactorInteger[n][[2,1]];f3[n_]:=First/@FactorInteger[n][[3,1]];f4[n_]:=Max[First/@FactorInteger[n]];lst={};Do[If[f0[n],AppendTo[lst,f4[n]]],{n,0,2*7!}];lst
%Y A176173 Cf. A006881, A007304, A070647, A096916, A096917, A096918, A096919, A176170, A176171, A176172
%K A176173 nonn
%O A176173 1,1
%A A176173 _Vladimir Joseph Stephan Orlovsky_, Apr 10 2010