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 A037399 #18 Aug 05 2021 07:00:55
%S A037399 1,2,3,4,5,28,80,85,86,98,115,160,172,213,266,331,345,532,691,699,705,
%T A037399 708,717,720,727,763,765,792,799,811,819,835,851,859,861,863,864,900,
%U A037399 916,928,1036,1061,1068,1085,1093,1128,1129,1130
%N A037399 Numbers k such that every base-6 digit of k is a base-8 digit of k.
%H A037399 Reinhard Zumkeller, <a href="/A037399/b037399.txt">Table of n, a(n) for n = 1..10000</a>
%t A037399 b68Q[n_]:=Module[{b6=Union[IntegerDigits[n,6]],b8=Union[IntegerDigits[ n,8]]}, And@@Table[ MemberQ[b8,b6[[i]]],{i,Length[b6]}]]; Select[Range[ 1200],b68Q] (* _Harvey P. Dale_, Mar 24 2012 *)
%o A037399 (Haskell)
%o A037399 import Data.List ((\\), nub)
%o A037399 a037399 n = a037399_list !! (n-1)
%o A037399 a037399_list = filter f [1..] where
%o A037399 f x = null $ nub (ds 6 x) \\ nub (ds 8 x)
%o A037399 ds b x = if x > 0 then d : ds b x' else [] where (x', d) = divMod x b
%o A037399 -- _Reinhard Zumkeller_, May 30 2013
%Y A037399 Cf. A007092, A007094.
%Y A037399 Cf. A037398, A037400, A037401.
%K A037399 nonn,base
%O A037399 1,2
%A A037399 _Clark Kimberling_