a(n)=aq^(n-1),1=a(3)=aq^2,2[a(5)+1]=2[aq^4+1]=a(4)a(6)=[aq^3][aq^5]=a^2q^8,2[aq^4+1]=2[aq^2*q^2+1]=2[q^2+1]=a^2q^8=(aq^2)^2*q^4=q^4,0=q^4-2q^2-2,q^2=[2+(2^2+2*4)^(1/2)]/2=[2+(12)^(1/2)]/2=1+3^(1/2),a=1/q^2=1/[1+3^(1/2)]=[3^(1/2)-1]/2,q=[1+3^(1/2)]^(1/2)或q=-[1+3^(1/2)]^(1/2).a(n)=([3^(1/2)-1]/2)[1+3^(1/2)]^[(n-1)/2]或a(n)=([3^(1/2)-1]/2)[1+3^(1/2)]^[(n-1)/2](-1)^(n-1),n=1,2,...
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