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 A284809 #6 Mar 12 2023 13:11:52
%S A284809 8,7,6,5,4,3,2,1,0,79,70,61,52,43,34,25,16,7,78,69,60,51,42,33,24,15,
%T A284809 6,77,68,59,50,41,32,23,14,5,76,67,58,49,40,31,22,13,4,75,66,57,48,39,
%U A284809 30,21,12,3,74,65,56,47,38,29,20,11,2,73,64,55,46,37,28,19
%N A284809 Write in base k, complement, reverse. Case k = 9.
%e A284809 a(14) = 34 because 14 in base 9 is 15, its complement in base 9 is 73 and the digit reverse is 37 that is 34 in base 10.
%p A284809 P:=proc(q,h) local a,b,k,n; print(h-1); for n from 1 to q do a:=convert(n,base,h); b:=0;
%p A284809 for k from 1 to nops(a) do a[k]:=h-1-a[k]; b:=h*b+a[k]; od; print(b); od; end: P(10^2,9);
%t A284809 Table[FromDigits[Reverse[8-#&/@IntegerDigits[n,9]],9],{n,0,70}] (* _Harvey P. Dale_, Mar 12 2023 *)
%Y A284809 Cf. A036044, A267193, A284810.
%K A284809 nonn,base,easy
%O A284809 0,1
%A A284809 _Paolo P. Lava_, Apr 03 2017