%I #12 Dec 14 2023 05:32:00
%S 1,1,-5,0,1,-3,-1,0,-3,1,-1,-4,1,1,-5,0,1,-3,-1,0,-3,1,-1,-4,1,1,-5,0,
%T 1,-3,-1,0,-3,1,-1,-4,1,1,-5,0,1,-3,-1,0,-3,1,-1,-4,1,1,-5,0,1,-3,-1,
%U 0,-3,1,-1,-4,1,1,-5,0,1,-3,-1,0,-3,1,-1,-4
%N Periodic {1,1,-5,0,1,-3,-1,0,-3,1,-1,-4}.
%C Diagonal sums of number triangle A115633.
%H <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (-1,-1,0,1,1,1).
%F G.f.: (1+2x-3x^2-4x^3-5x^4-4x^5)/((1-x^3)*(1+x+x^2+x^3)); a(n)=sum{k=0..floor(n/2), A115633(n-k, k)}.
%K easy,sign
%O 0,3
%A _Paul Barry_, Jan 27 2006