Talk:Euler's totient function

Some motivation and derivation of the formula would make this article more useful.--MCrawford 13:18, 20 June 2006 (EDT)

I changed the part under "Notation". It surely is not best as it is now, but the old one was surely wrong:

- is _not_ a capital letter "Phi", but still a lower case character; compare: to .

- is about as widely spread as , e.g. the normal Wikipedia and more than half of my books prefer . --ZetaX 10:58, 30 January 2008 (EST)