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 A171055 #11 Mar 31 2017 00:45:03
%S A171055 2,3,5,7,11,13,17,16,23,26,31,37,41,43,47,53,56,91,97,71,73,76,83,86,
%T A171055 67,101,103,107,106,113,127,131,137,136,146,151,157,193,197,173,176,
%U A171055 181,161,163,167,166,211,223,227,226,233,236,241,251,257,293
%N A171055 In the sequence of prime numbers, replace all the '9' digits with '6' and vice versa.
%H A171055 Vincenzo Librandi, <a href="/A171055/b171055.txt">Table of n, a(n) for n = 1..1000</a>
%t A171055 FromDigits[IntegerDigits[#] /. {9 -> p, 6 -> q} /. {p -> 6, q -> 9}] & /@ Prime[Range[100]] (* _Vincenzo Librandi_, Jul 06 2012, after _Harvey P. Dale_ in similar sequences *)
%o A171055 (PARI) a(n)=my(v=[0,1,2,3,4,5,9,7,8,6]);subst(Pol(apply(k->v[k+1], digits(prime(n)))),'x,10) \\ _Charles R Greathouse IV_, Jul 31 2013
%K A171055 nonn,base,easy
%O A171055 1,1
%A A171055 _N. J. A. Sloane_ and _Vincenzo Librandi_, Sep 04 2010