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 A121032 #19 Nov 02 2022 13:56:12
%S A121032 12,120,312,612,912,1128,1200,1212,1224,1236,1248,1260,1272,1284,1296,
%T A121032 1512,1812,2112,2124,2412,2712,3012,3120,3312,3612,3912,4128,4212,
%U A121032 4512,4812,5112,5124,5412,5712,6012,6120,6312,6612,6912,7128,7212,7512,7812
%N A121032 Multiples of 12 containing a 12 in their decimal representation.
%H A121032 Reinhard Zumkeller, <a href="/A121032/b121032.txt">Table of n, a(n) for n = 1..10000</a>
%H A121032 <a href="/index/Ar#10-automatic">Index entries for 10-automatic sequences</a>.
%F A121032 a(n) ~ 12n. - _Charles R Greathouse IV_, Nov 02 2022
%t A121032 Select[12*Range[700],SequenceCount[IntegerDigits[#],{1,2}]>0&] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Oct 25 2017 *)
%o A121032 (Haskell)
%o A121032 import Data.List (isInfixOf)
%o A121032 a121032 n = a121032_list !! (n-1)
%o A121032 a121032_list = filter ((isInfixOf "12") . show) a008594_list
%o A121032 -- _Reinhard Zumkeller_, Dec 12 2012
%o A121032 (PARI) is(n)=if(n%12, return(0)); while(n>11, if(n%100==12, return(1)); n\=10); 0 \\ _Charles R Greathouse IV_, Feb 12 2017
%Y A121032 Subsequence of A008594.
%Y A121032 Cf. A121041, A011531, A121022, A121023, A121024, A121025, A121026, A121027, A121028, A121029, A121030, A121031, A121033, A121034, A121035, A121036, A121037, A121038, A121039, A121040.
%K A121032 nonn,base,look,easy
%O A121032 1,1
%A A121032 _Reinhard Zumkeller_, Jul 21 2006
%E A121032 Data fixed by _Reinhard Zumkeller_, Dec 12 2012