For a prime $Q$ lying over a prime $P$, I have seen the ramification index of $Q$ over $P$ denoted by $e(Q|P)$ and the inertial degree of $Q$ over $P$ by $f(Q|P)$.
What is the origin of the notations $e$ and $f$?
Sign up using Google
Sign up using Facebook
Sign up using Stack Exchange
3 years ago