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 A161945 #13 May 08 2018 03:17:27
%S A161945 91,115,117,119,121,141,143,183,185,201,203,205,213,215,217,243,245,
%T A161945 285,287,295,297,299,301,319,321,323,325,339,341,361,391,403,411,413,
%U A161945 423,425,451,469,471,473,481,493,511,513,515,525,527,529,531,533,535,549
%N A161945 Numbers n with property that three consecutive odd numbers {n,n+2,n+4} are all composite.
%e A161945 143 is in the sequence because 143=11*13, 145=5*29, 147=3*49. [_Emeric Deutsch_, Jun 27 2009]
%p A161945 a:= proc(n) if not (isprime(2*n-1) or isprime(2*n+1) or isprime(2*n+3)) then 2*n-1 end if end proc: seq(a(n), n = 2 .. 300); # _Emeric Deutsch_, Jun 27 2009
%t A161945 fQ[n_]:=!PrimeQ[n]&&!PrimeQ[n+2]&&!PrimeQ[n+4];Select[Range[3,1000,2],fQ] (* _Vladimir Joseph Stephan Orlovsky_, Apr 16 2011 *)
%K A161945 nonn
%O A161945 1,1
%A A161945 _Zak Seidov_, Jun 22 2009