On the solution to the separated equation in the 3-particle Calogero-Moser problem

We propose the exact solution of the equation in separated variable which appears in the process of constructing solutions to the quantum Calogero-Moser three-particle problem with elliptic two-particle potential $g(g-1)\wp(q)$. This solution is found for special values of coupling constants $g\in {\mathbb Z}, \, g>1$. It can be used for solving three-paricle CM problem under appropriate boundary conditions.