This number lies in the n-th cyclotomic field — and in fact in its real subfield, which is a totally real field of degree over the rational numbersBingo! Note, this has been fixed on Wikipedia a long time ago. This also highlights the danger, and potential hilarity of Wikipedia clones.
where φ(n) is Euler's toilet function.
Thursday, July 05, 2012
Euler's toilet function
I was recently reading the Wikipedia article on Euler's totient function, and thought that I couldn't be the only person who initially read it as "Euler's toilet function." A quick Google search later turned up this Wikipedia clone with the key line: