Thread: phi(n) divides n-1 implies n is prime

Prove that if then is prime, where . is the Euler's totient function.

I am able to show that is square-free under the above condition.

Originally Posted by abhishekkgp

Prove that if then is prime, where . is the Euler's totient function.

I am able to show that is square-free under the above condition.

Lehmer's conjecture

Originally Posted by princeps

Lehmer's conjecture

Thank You. I did not know its an unsolved problem or I would not post it.