👉 In mathematics, a Dirichlet character is a specific function that maps from the integers to the set of positive rational numbers. It is often used in number theory and algebraic geometry to study modular forms or other special types of functions. The Dirichlet character $\chi(n)$ is defined as follows: $\chi(n) = \begin{cases} 1 & \text{if } n \equiv 1 \pmod{4}, \\ 0 & \text{otherwise}. \end
