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 A222250 #10 Mar 30 2017 22:40:01
%S A222250 0,1,2,3,4,5,8,7,6,9,10,11,12,13,14,15,18,17,16,19,20,21,22,23,24,25,
%T A222250 28,27,26,29,30,31,32,33,34,35,38,37,36,39,40,41,42,43,44,45,48,47,46,
%U A222250 49,50,51,52,53,54,55,58,57,56,59,80,81,82,83,84,85,88,87,86,89,70,71,72,73,74,75
%N A222250 In the number n, replace all (decimal) digits '6' with '8' and vice versa.
%C A222250 The map which is applied to primes in A171047.
%H A222250 Vincenzo Librandi, <a href="/A222250/b222250.txt">Table of n, a(n) for n = 0..1000</a>
%t A222250 a[n_]:= IntegerDigits[n]/.{6->8, 8->6} // FromDigits; Table[a[n], {n, 0, 80}] (* _Vincenzo Librandi_, Jul 31 2013 *)
%o A222250 (PARI) A222250(n,d=[0, 1, 2, 3, 4, 5, 8, 7, 6, 9])=sum(i=1,#n=digits(n),d[n[i]+1]*10^(#n-i),!n*d[1]) \\ N.B.: digits(0)=[] in PARI (v.2.6)
%Y A222250 Cf. A222210-A222254; A171013-A171016, A175770, A171018-A171057.
%K A222250 nonn,base,easy
%O A222250 0,3
%A A222250 _M. F. Hasler_, Feb 13 2013