%I A117373
%S A117373 1,2,3,1,2,3,1,2,3,1,2,3,1,2,3,1,2,3,1,2,3,1,2,3,1,2,3,1,2,3,1,2,3,1,2,
%T A117373 3,1,2,3,1,2,3,1,2,3,1,2,3,1,2,3,1,2,3,1
%V A117373 1,-2,-3,-1,2,3,1,-2,-3,-1,2,3,1,-2,-3,-1,2,3,1,-2,-3,-1,2,3,1,-2,-3,-1,
               2,3,1,-2,-3,-1,
%W A117373 2,3,1,-2,-3,-1,2,3,1,-2,-3,-1,2,3,1,-2,-3,-1,2,3,1
%N A117373 Expansion of (1-3x)/(1-x+x^2).
%C A117373 Row sums of number triangle A117372.
%C A117373 Periodic sequence with period {1, -2, -3, -1, 2, 3}. [From Philippe DELEHAM 
               (kolotoko(AT)wanadoo.fr), Nov 03 2008]
%H A117373 <a href="Sindx_Rea.html#recLCC">Index entries for sequences related to 
               linear recurrences with constant coefficients</a>
%H A117373 Tanya Khovanova, <a href="http://www.tanyakhovanova.com/RecursiveSequences/
               RecursiveSequences.html">Recursive Sequences</a>
%F A117373 a(n)=sum{k=0..n, (-1)^(n-k)(C(k,n-k)+3*C(k, n-k-1))}
%F A117373 a(n)=1/6*{2*[n mod 6]-[(n+1) mod 6]-3*[(n+2) mod 6]-2*[(n+3) mod 6]+[(n+4) 
               mod 6]+3*[(n+5) mod 6]}, with n>=1. - Paolo P. Lava (ppl(AT)spl.at), 
               Apr 27 2007
%F A117373 a(n)=a(n-1)-a(n-2); a(0)=1, a(1)=-2 . [From Philippe DELEHAM (kolotoko(AT)wanadoo.fr), 
               Nov 03 2008]
%Y A117373 Sequence in context: A047896 A073645 A082846 this_sequence A132677 A010882 
               A106590
%Y A117373 Adjacent sequences: A117370 A117371 A117372 this_sequence A117374 A117375 
               A117376
%K A117373 easy,sign
%O A117373 0,2
%A A117373 Paul Barry (pbarry(AT)wit.ie), Mar 10 2006