Proving n/Φ(n)=2q/q-1: A Proof Using Euler's Totient Function

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Hello, can anyone help with this question? Thank you.


Let n even perfect number and q prime. Show that n/Φ(n)=2q/q-1.

Φ(n) is the Euler function-totient (the number of positive integers less than or equal to n that are coprime to n)


I have tried euler-euclid theorem but could not get it.
 
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2q/(q-1) is different for different primes q, so you must have some additional condition on what q is (unless you really meant without the parentheses, in which case 2q/q-1 = 1 which makes no sense). Unless you're trying to show such a q exists?
 


phi(n)=phi[2^(k-1)q] where q=(2^k)-1

phi(n)=phi(2^(k-1))phi(q)=phi(2^(k-1))(q-1)

Is there any property I can use to finish this?
 


What's phi(2^(k-1))? There's a formula for phi for powers of a prime. (It's also the number of odd integers less than 2^(k-1)).
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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