Talk:Sum of Euler Phi Function over Divisors

The bit `As each of the integers $1, 2, \ldots, n$ lies in exactly one of the $S_{d_j}$, it follows that:` is not at all clear, and needs its own paragraph, perhaps even a lemma.


 * You're right, it is a bit handwavey. Needs to be rewritten.


 * BTW please sign your posts on chat pages. --prime mover (talk) 06:55, 7 October 2014 (UTC)