Computing isolated coefficients of the $j$-function

Abstract

We consider the problem of efficiently computing isolated coefficients $c_n$ in the Fourier series of the elliptic modular function $j(\tau )$. We show that a hybrid numerical-modular method with complexity $n^{1+o(1)}$ is efficient in practice. As an application, we locate the first few values of $c_n$ that are prime, the first occurring at $n=457871$.

References in corpus (1)

• Efficient implementation of the Hardy-Ramanujan-Rademacher formula