1/5 = [0.2]10 = [0.1]5 = [0.151515...]7
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とあるけれど、
1/5 = [0.2]10 = [0.1]5 = [0.12541254...]7
1/4 = [0.151515...]7
じゃないかな。
1/5=( 7/5)/7=(1+2/5)/7=(1/7)×(1+2/5)
2/5=(14/5)/7=(2+4/5)/7=(1/7)×(2+4/5)
4/5=(28/5)/7=(5+3/5)/7=(1/7)×(5+3/5)
3/5=(21/5)/7=(4+1/5)/7=(1/7)×(4+1/5)
roop
1/5=1/7(1+1/7(2+1/7(5+1/7(4+1/7(1+~
=1×(1/71)+2×(1/72)+5×(1/73)+4×(1/74)+1×～
一方、
1/4=( 7/4)/7=(1+3/4)/7=(1/7)×(1+3/4)
3/4=(21/4)/7=(5+1/4)/7=(1/7)×(5+1/4)
roop
