πの連分数展開は
[3:7,1,15,1,292,・・・]
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exp(x)の連分数展開は
[1:2/1,x^2/6+,x^2/10+,x^2/14+,・・・]
x=1に対しては
e=[1:2x/(2-x)+,1/6+,1/10+,1/14+,・・・]