Schellekens' conjecture on holomorphic tame vertex algebras of central charge 24

A holomorphic vertex algebra is a vertex algebra with no nontrivial modules, and tameness is the finiteness and regularity condition assumed in the source. The central charge is the scalar $24$ appearing in the Virasoro algebra.

Schellekens' conjecture. There are exactly $71$ holomorphic tame vertex algebras of central charge $24$.

This conjecture concerns the classification of holomorphic vertex algebras at central charge $24$. It is motivated by the $24$ examples obtained from the Niemeier lattice construction and by Schellekens' classification work and subsequent evidence; its resolution is not established in the supplied text.