■間引いたフィボナッチ数列(その19)
フィボナッチ数列
f(x)=(x)/(1-x-x^2)=(1/√5)/(1-αx)-(1/√5)/(1-βx)
α=(1+√5)/2、β=(1-√5)/2
an=1/√5・{α^n-β^n}
間引いたフィボナッチ数列{F2^n}、すなわち、1,1,3,21,987,・・・
α=(1+√5)/2、β=(1-√5)/2
F2^n=1/√5・{α^2^n-β^2^n}
では
Σ1/F2^n=(7-√5)/2
が成り立つ
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F(2^n-1)L(2^n)=F(2^n+1-1)+1
ΠL2^i=F(2^n+1)
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P=(1+1/2)(1+1/13)(1+1/610)・・・=Π(1+1/F2^n+1-1)
=Π(1+F(2^n+1-1)/(F2^n+1-1)
=Π(F(2^n-1)L(2^n))/(F2^n+1-1)
=Π(F(2^n-1)/(F2^n+1-1)・F2(2^m+1)
=F(2^m+1)/F(2^m+1-1)→φ
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