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 A131733 #10 Aug 26 2015 00:42:03
%S A131733 1,0,0,0,2,2,4,4,6,10,10,14,16,16,18,22,26,26,30,32,32,36,38,42,48,50,
%T A131733 50,52,52,54,66,68,72,72,80,80,84,88,90,94,98,98,106,106,108,108,118,
%U A131733 128,130,130,132,136,136,144,148,152,156,156,160,162,162,170
%N A131733 Primes (A000040) - odds (A005408).
%F A131733 a(n) = A000040(n)-2n+1.
%p A131733 A131733 := proc(n) ithprime(n)-2*n+1 ; end proc: # _R. J. Mathar_, Jul 10 2011
%t A131733 With[{nn=70},Prime[Range[nn]]-Range[1,2nn,2]] (* _Harvey P. Dale_, Jun 12 2013 *)
%K A131733 nonn,easy
%O A131733 1,5
%A A131733 _Paul Curtz_, Sep 17 2007