%I #5 Jun 27 2013 09:57:24
%S 1,-3,-3,7,7,-9,-9,47,47,-123,-123,161,161,-843,-843,2207,2207,-2889,
%T -2889,15127,15127,-39603,-39603,51841,51841,-271443,-271443,710647,
%U 710647,-930249,-930249,4870847,4870847,-12752043,-12752043
%N a(n)=A128056(n)/A128055(n).
%F a(n)=(-1)^C(n+1,2)*(F(n-1)+F(n+1))(5/6-cos(pi*n/3)/3)(1+(-1)^n)/2+(F(n)+F(n+2))(5/6-cos(pi*(n+1)/3)/3)(1-(-1)^n)/2.
%F Empirical g.f.: -(x-1) * (x^10-2*x^9-5*x^8+2*x^7+9*x^6+9*x^4+2*x^3-5*x^2-2*x+1) / ((x^4+3*x^2+1)*(x^8-3*x^6+8*x^4-3*x^2+1)). - _Colin Barker_, Jun 27 2013
%Y Cf. A128052.
%K easy,sign
%O 0,2
%A _Paul Barry_, Feb 13 2007
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