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 A222230 #10 Mar 31 2017 00:22:44
%S A222230 0,1,6,3,4,5,2,7,8,9,10,11,16,13,14,15,12,17,18,19,60,61,66,63,64,65,
%T A222230 62,67,68,69,30,31,36,33,34,35,32,37,38,39,40,41,46,43,44,45,42,47,48,
%U A222230 49,50,51,56,53,54,55,52,57,58,59,20,21,26,23,24,25,22,27,28,29,70,71,76,73,74,75
%N A222230 In the number n, replace all (decimal) digits '2' with '6' and vice versa.
%C A222230 The map which is applied to primes in A171030.
%H A222230 Vincenzo Librandi, <a href="/A222230/b222230.txt">Table of n, a(n) for n = 0..1000</a>
%t A222230 a[n_]:= IntegerDigits[n]/.{2->6, 6->2} // FromDigits; Table[a[n], {n, 0, 80}] (* _Vincenzo Librandi_, Jul 30 2013 *)
%o A222230 (PARI) A222230(n,d=[0,1,6,3,4,5,2,7,8,9])=sum(i=1, #n=digits(n), d[n[i]+1]*10^(#n-i)) \\ gives correct value for n=0 iff d[1]=0, since digits(0)=[] in PARI (v.2.6)
%Y A222230 Cf. A222210-A222254; A171013-A171016, A175770, A171018-A171057.
%K A222230 nonn,base,easy
%O A222230 0,3
%A A222230 _M. F. Hasler_, Feb 12 2013