  We study the set G of growth rates of of ideal Coxeter groups in hyperbolic
3-space which consists of real algebraic integers greater than 1. We show that
(1) G is unbounded above while it has the minimum, (2) any element of G is a
Perron number, and (3) growth rates of of ideal Coxeter groups with $n$
generators are located in the closed interval $[n-3, n-1]$.

Geometric Topology