True or false (and of course why):
Euler's totient function implies all its range for odd variables.
I proved that for all n>1 odd numbers:
φ(n)=φ(2n).
But it's not enough. Because I should prove that for all even n I can find an odd k for which:
φ(n)=φ(2k). But I can't see it.
Please help me!
Any help would be appreciated.
Thanks!