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A050100 a(n) = floor(a(n-1)/3) if this is positive and not yet in the sequence, otherwise a(n) = 10*a(n-1).

%I A050100 #12 Oct 05 2019 16:35:10
%S A050100 1,10,3,30,300,100,33,11,110,36,12,4,40,13,130,43,14,140,46,15,5,50,
%T A050100 16,160,53,17,170,56,18,6,2,20,200,66,22,7,70,23,230,76,25,8,80,26,
%U A050100 260,86,28,9,90,900,9000,3000,1000,333,111,37,370
%N A050100 a(n) = floor(a(n-1)/3) if this is positive and not yet in the sequence, otherwise a(n) = 10*a(n-1).
%H A050100 Ivan Neretin, <a href="/A050100/b050100.txt">Table of n, a(n) for n = 1..10000</a>
%t A050100 Rest@Nest[Append[#, If[FreeQ[#, r = Quotient[#[[-1]], 3]], r, 10 #[[-1]]]] &, {0, 1}, 56] (* _Ivan Neretin_, Jul 31 2016 *)
%o A050100 (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]=10*v[i-1]; next); for(j=1, i-1, if(v[j]==t, v[i]=10*v[i-1]; next(2))); v[i]=t); v \\ _Charles R Greathouse IV_, Jul 31 2016
%Y A050100 Cf. A050000 and references therein.
%K A050100 nonn
%O A050100 1,2
%A A050100 _Clark Kimberling_