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 A050088 #12 Oct 05 2019 11:31:44 %S A050088 1,6,2,12,4,24,8,48,16,5,30,10,3,18,108,36,216,72,432,144,864,288,96, %T A050088 32,192,64,21,7,42,14,84,28,9,54,324,1944,648,3888,1296,7776,2592, %U A050088 15552,5184,1728,576,3456,1152,384,128,768,256,85,510 %N A050088 a(n) = floor(a(n-1)/3) if this is positive and not yet in the sequence, otherwise a(n) = 6*a(n-1). %H A050088 Ivan Neretin, <a href="/A050088/b050088.txt">Table of n, a(n) for n = 1..10000</a> %t A050088 Rest@Nest[Append[#, If[FreeQ[#, r = Quotient[#[[-1]], 3]], r, 6 #[[-1]]]] &, {0, 1}, 52] (* _Ivan Neretin_, Jul 31 2016 *) %o A050088 (PARI) first(n)=my(v=vector(n),t); v[1]=1; for(i=2,n, t=v[i-1]\3; if(t<2, v[i]=6*v[i-1]; next); for(j=1,i-1, if(v[j]==t, v[i]=6*v[i-1]; next(2))); v[i]=t); v \\ _Charles R Greathouse IV_, Jul 31 2016 %Y A050088 Cf. A050000 and references therein. %K A050088 nonn %O A050088 1,2 %A A050088 _Clark Kimberling_