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 A171014 #12 Mar 31 2017 20:32:51
%S A171014 0,3,5,7,11,13,17,19,3,9,31,37,41,43,47,53,59,61,67,71,73,79,83,89,97,
%T A171014 121,123,127,129,113,107,131,137,139,149,151,157,163,167,173,179,181,
%U A171014 191,193,197,199,11,3,7,9,33,39,41,51,57,63,69,71,77,81,83,93
%N A171014 In the sequence of prime numbers, replace all the '2' digits with '0' and vice versa.
%H A171014 Vincenzo Librandi, <a href="/A171014/b171014.txt">Table of n, a(n) for n = 1..1000</a>
%t A171014 FromDigits[IntegerDigits[#]/.{2->p,0->q}/.{p->0,q->2}]&/@ Prime[ Range[70]] (* _Harvey P. Dale_, Dec 11 2011 *)
%o A171014 (PARI) a(n)=my(v=[2,1,0,3,4,5,6,7,8,9]);apply(k->v[k+1],digits(prime(n))) \\ _Charles R Greathouse IV_, Jul 16 2013
%K A171014 nonn,base,easy
%O A171014 1,2
%A A171014 _N. J. A. Sloane_ and _Vincenzo Librandi_, Sep 04 2010