%I #12 Oct 05 2019 11:33:04

%S 1,5,2,10,50,25,12,6,3,15,7,35,17,8,4,20,100,500,250,125,62,31,155,77,

%T 38,19,9,45,22,11,55,27,13,65,32,16,80,40,200,1000,5000,2500,1250,625,

%U 312,156,78,39,195,97,48,24,120,60,30,150

%N a(n) = floor(a(n-1)/2) if this is not among 0, a(1), ..., a(n-2); otherwise a(n) = 5*a(n-1).

%H Ivan Neretin, <a href="/A050004/b050004.txt">Table of n, a(n) for n = 1..10000</a>

%t Rest@Nest[Append[#, If[FreeQ[#, r = Quotient[#[[-1]], 2]], r, 5 #[[-1]]]] &, {0, 1}, 55] (* _Ivan Neretin_, Jul 31 2016 *)

%Y Cf. A050000 and references therein.

%K nonn,easy

%O 1,2

%A _Clark Kimberling_