Given two positive integer numbers m,n, show that m/n can't have period b−1 in base b.












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Given two positive integer numbers $m,n$, show that $frac{m}{n}$ can't have period $b-1$ in base $b$.



MY ATTEMPT: wlog $m<n$, then suppose $frac{m}{n}=0,a_1a_2...a_{b-1}$. Multiplying both sides by $b^{b-1}-1$ we obtain $frac{m(b^{b-1}-1)}{n}=a_1...a_{b-1}$ with $a_i in {0,1,2,...,b-1}$. How can I conclude?










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    0














    Given two positive integer numbers $m,n$, show that $frac{m}{n}$ can't have period $b-1$ in base $b$.



    MY ATTEMPT: wlog $m<n$, then suppose $frac{m}{n}=0,a_1a_2...a_{b-1}$. Multiplying both sides by $b^{b-1}-1$ we obtain $frac{m(b^{b-1}-1)}{n}=a_1...a_{b-1}$ with $a_i in {0,1,2,...,b-1}$. How can I conclude?










    share|cite|improve this question

























      0












      0








      0







      Given two positive integer numbers $m,n$, show that $frac{m}{n}$ can't have period $b-1$ in base $b$.



      MY ATTEMPT: wlog $m<n$, then suppose $frac{m}{n}=0,a_1a_2...a_{b-1}$. Multiplying both sides by $b^{b-1}-1$ we obtain $frac{m(b^{b-1}-1)}{n}=a_1...a_{b-1}$ with $a_i in {0,1,2,...,b-1}$. How can I conclude?










      share|cite|improve this question













      Given two positive integer numbers $m,n$, show that $frac{m}{n}$ can't have period $b-1$ in base $b$.



      MY ATTEMPT: wlog $m<n$, then suppose $frac{m}{n}=0,a_1a_2...a_{b-1}$. Multiplying both sides by $b^{b-1}-1$ we obtain $frac{m(b^{b-1}-1)}{n}=a_1...a_{b-1}$ with $a_i in {0,1,2,...,b-1}$. How can I conclude?







      number-theory






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      asked Jan 4 at 13:14









      LanceLance

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          I may miss something...



          But $overline{0,123456789123456789...}^{10}$ is a rational having a period equal to $9$ written in base $10$.






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            1 Answer
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            active

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            active

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            1














            I may miss something...



            But $overline{0,123456789123456789...}^{10}$ is a rational having a period equal to $9$ written in base $10$.






            share|cite|improve this answer


























              1














              I may miss something...



              But $overline{0,123456789123456789...}^{10}$ is a rational having a period equal to $9$ written in base $10$.






              share|cite|improve this answer
























                1












                1








                1






                I may miss something...



                But $overline{0,123456789123456789...}^{10}$ is a rational having a period equal to $9$ written in base $10$.






                share|cite|improve this answer












                I may miss something...



                But $overline{0,123456789123456789...}^{10}$ is a rational having a period equal to $9$ written in base $10$.







                share|cite|improve this answer












                share|cite|improve this answer



                share|cite|improve this answer










                answered Jan 4 at 13:21









                mathcounterexamples.netmathcounterexamples.net

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                25.3k21953






























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