%I A081410
%S A081410 1,1,2,4,8,12,21,35,56,92,150,242,393,637,1030,1668,2700,4368,7069,
%T A081410 11439,18508,29948,48458,78406,126865,205273,332138,537412,869552,
%U A081410 1406964,2276517,3683483,5960000,9643484,15603486,25246970,40850457
%N A081410 a(1)=a(2)=1; a(n)=a(n-1)+a(n-2) + n (mod 3).
%F A081410 a(n)=floor(C*F(n))+b(n) where C=(9-sqrt(5))/4, F(n) is the n-th Fibonacci 
               number and b(n) is the 6-periodic sequence (0, 0, -1, -1, 0, -1)
%F A081410 G.f.: (2x^4+1) / [(1-x^3)(1-x-x^2)].
%Y A081410 Cf. A004695.
%Y A081410 Sequence in context: A131770 A163489 A076651 this_sequence A027677 A103787 
               A032473
%Y A081410 Adjacent sequences: A081407 A081408 A081409 this_sequence A081411 A081412 
               A081413
%K A081410 nonn
%O A081410 1,3
%A A081410 Benoit Cloitre (benoit7848c(AT)orange.fr), Apr 20 2003