For questions on Dirichlet series.
In mathematics, a Dirichlet series is any series of the form $$ \sum_{n=1}^{\infty} \frac{a_n}{n^s}, $$ where $s$ and $a_n$ are complex numbers and $n = 1, 2, 3, \dots$ . It is a special case of general Dirichlet series.
Dirichlet series play a variety of important roles in analytic number theory. The most usually seen definition of the Riemann $\zeta$ function is a Dirichlet series with $a_n=1$, as also are the Dirichlet $L$-functions.
It is conjectured that the Selberg class of series obeys the generalized Riemann hypothesis. The series is named in honor of Johann Peter Gustav Lejeune Dirichlet.
