Johann Peter Gustav Lejeune Dirichlet
The life of Johann Peter Gustav Lejeune Dirichlet - Defined the Modern Function.
Dirichlet Series
A generalization of the Zeta function.
\[ F(s) = \sum_{n=1}^\infty \frac{a_n}{n^s} \]
Class Number Formula
Relating algebraic number theory quantities to L-function values.
\[ h = \frac{w\sqrt{|D|}}{2\pi} L(1, \chi) \]
Sources: https://mathshistory.st-andrews.ac.uk/Biographies/Dirichlet/
