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 A171046 #10 Mar 31 2017 00:52:01
%S A171046 2,3,8,7,11,13,17,19,23,29,31,37,41,43,47,83,89,61,67,71,73,79,53,59,
%T A171046 97,101,103,107,109,113,127,131,137,139,149,181,187,163,167,173,179,
%U A171046 151,191,193,197,199,211,223,227,229,233,239,241,281,287,263
%N A171046 In the sequence of prime numbers, replace all the '8' digits with '5' and vice versa.
%H A171046 Harvey P. Dale, <a href="/A171046/b171046.txt">Table of n, a(n) for n = 1..1000</a>
%t A171046 FromDigits[IntegerDigits[#]/.{5->Q,8->P}/.{Q->8,P->5}]&/@ Prime[ Range[ 60]] (* _Harvey P. Dale_, Nov 12 2011 *)
%o A171046 (PARI) a(n)=my(v=[0,1,2,3,4,8,6,7,5,9]);subst(Pol(apply(k->v[k+1], digits(prime(n)))),'x,10) \\ _Charles R Greathouse IV_, Jul 31 2013
%K A171046 nonn,base,easy
%O A171046 1,1
%A A171046 _N. J. A. Sloane_ and _Vincenzo Librandi_, Sep 04 2010