OFFSET
1,2
LINKS
Ivan Neretin, Table of n, a(n) for n = 1..10000
MATHEMATICA
Rest@Nest[Append[#, If[MemberQ[#, c = Quotient[#[[-1]], 2]], 10*#[[-1]], c]] &, {0, 1}, 54] (* Ivan Neretin, Sep 06 2015 *)
PROG
(PARI) first(n)=my(v=vector(n), t); v[1]=1; for(i=2, n, t=v[i-1]\2; 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
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved