%I A072561
%S A072561 1,3,4,6,7,9,10,12,13,15,19,21,22,24,25,27,28,30,31,33,37,39,40,42,43,
%T A072561 45,46,48,49,51,55,57,58,60,61,63,64,66,67,69,73,75,76,78,79,81,82,84,
%U A072561 85,87,91,93,94,96,97,99,100,102,103,105,109,111,112,114,115,117,118
%N A072561 Denominators of w(n) equals 3 where w(1)=w(2)=w(3)=1, w(n)=(w(n-1)*w(n-2)+(w(n-1)+w(n-2))/
               3) / w(n-3).
%C A072561 Denominators of w(k) are 1, 3 or 9.
%F A072561 lim n -> infinity a(n)/n = 9/5. sequence contains numbers of form (1+18k), 
               (3+18k), (4+18k), (6+18k), (7+18k), (9+18k), (10+18k), (12+18k), 
               (13+18k), (15+18k) k>=0.
%Y A072561 Cf. A072560, A072557.
%Y A072561 Sequence in context: A140098 A059559 A103877 this_sequence A141206 A140100 
               A093610
%Y A072561 Adjacent sequences: A072558 A072559 A072560 this_sequence A072562 A072563 
               A072564
%K A072561 nonn
%O A072561 1,2
%A A072561 Benoit Cloitre (benoit7848c(AT)orange.fr), Aug 06 2002
%E A072561 Corrected by Franklin T. Adams-Watters, Oct 25 2006