cp's OEIS Frontend

A132139 a(n) = f(n,1) with f(m,x) = if m<3 then (if m=1 then x else 0) else (if m mod 3 = 0 then 0 else f([m/3], x*(1 + m mod 3) + 1)).

%I A132139 #4 Mar 30 2012 18:50:58
%S A132139 1,0,0,3,4,0,0,0,0,0,0,0,7,9,0,10,13,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
%T A132139 0,0,0,0,0,0,15,19,0,21,27,0,0,0,0,22,28,0,31,40,0,0,0,0,0,0,0,0,0,0,
%U A132139 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
%N A132139 a(n) = f(n,1) with f(m,x) = if m<3 then (if m=1 then x else 0) else (if m mod 3 = 0 then 0 else f([m/3], x*(1 + m mod 3) + 1)).
%H A132139 R. Zumkeller, <a href="/A132139/b132139.txt">Table of n, a(n) for n = 1..10000</a>
%K A132139 nonn
%O A132139 1,4
%A A132139 _Reinhard Zumkeller_, Aug 20 2007