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 A222248 #10 Mar 30 2017 22:40:51
%S A222248 0,1,2,3,4,9,6,7,8,5,10,11,12,13,14,19,16,17,18,15,20,21,22,23,24,29,
%T A222248 26,27,28,25,30,31,32,33,34,39,36,37,38,35,40,41,42,43,44,49,46,47,48,
%U A222248 45,90,91,92,93,94,99,96,97,98,95,60,61,62,63,64,69,66,67,68,65,70,71,72,73,74,79
%N A222248 In the number n, replace all (decimal) digits '5' with '9' and vice versa.
%C A222248 The map which is applied to primes in A171054.
%H A222248 Vincenzo Librandi, <a href="/A222248/b222248.txt">Table of n, a(n) for n = 0..1000</a>
%t A222248 a[n_]:= IntegerDigits[n]/.{5->9, 9->5} // FromDigits; Table[a[n], {n, 0, 80}] (* _Vincenzo Librandi_, Jul 31 2013 *)
%o A222248 (PARI) A222248(n,d=[0, 1, 2, 3, 4, 9, 6, 7, 8, 5])=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 A222248 Cf. A222210-A222254; A171013-A171016, A175770, A171018-A171057.
%K A222248 nonn,base,easy
%O A222248 0,3
%A A222248 _M. F. Hasler_, Feb 13 2013