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 A222218 #12 Aug 03 2025 00:05:40
%S A222218 9,1,2,3,4,5,6,7,8,0,19,11,12,13,14,15,16,17,18,10,29,21,22,23,24,25,
%T A222218 26,27,28,20,39,31,32,33,34,35,36,37,38,30,49,41,42,43,44,45,46,47,48,
%U A222218 40,59,51,52,53,54,55,56,57,58,50,69,61,62,63,64,65,66,67,68,60,79,71,72,73,74,75
%N A222218 In the number n, replace all (decimal) digits '0' with '9' and vice versa.
%C A222218 The map which is applied to primes in A171049.
%H A222218 Vincenzo Librandi, <a href="/A222218/b222218.txt">Table of n, a(n) for n = 0..1000</a>
%t A222218 a[n_]:= IntegerDigits[n]/.{0->9, 9->0} // FromDigits; Table[a[n], {n, 0, 80}] (* _Vincenzo Librandi_, Jul 29 2013 *)
%o A222218 (PARI) A222218(n,d=[9,1,2,3,4,5,6,7,8,0])={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 A222218 Cf. A222210-A222254; A171013-A171016, A175770, A171018-A171057.
%K A222218 nonn,easy,base
%O A222218 0,1
%A A222218 _M. F. Hasler_, Feb 12 2013