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 A175191 #15 Oct 02 2020 18:38:00
%S A175191 1,3,2,1,2,1,2,1,1,2,1,1,2,1,1,1,2,1,1,2,1,1,1,1,1,2,1,2,1,1,1,1,2,1,
%T A175191 2,1,1,1,1,1,2,1,2,1,2,1,1,1,2,1,1,2,1,1,1,1,2,1,1,2,1,1,1,2,1,1,1,1,
%U A175191 2,1,1,1,1,1,1,1,1,1,1,1,2,1,2,1,1,1,1,1,2,1,1,1,1,1,1,1,1,2,1,1,1,1,1,2,1
%N A175191 a(n) = the smallest positive integer such that (the n-th prime)+2*a(n) is composite.
%C A175191 Every term except a(2) (which is 3) is either 1 or 2.
%H A175191 G. C. Greubel, <a href="/A175191/b175191.txt">Table of n, a(n) for n = 1..1000</a>
%p A175191 a:= n-> `if`(n=2, 3, `if`(isprime(ithprime(n)+2), 2, 1)):
%p A175191 seq(a(n), n=1..105); # _Alois P. Heinz_, Oct 02 2020
%t A175191 spi[n_]:=Module[{i=1},While[PrimeQ[Prime[n]+2i],i++];i]; Array[spi,110] (* _Harvey P. Dale_, Apr 23 2012 *)
%K A175191 nonn
%O A175191 1,2
%A A175191 _Leroy Quet_, Mar 01 2010
%E A175191 Extended by _Ray Chandler_, Mar 04 2010