Big Omega function

The notation $\Omega (\text{ })\,\!$ has at least three meanings in mathematics:

$f = \Omega (g)\,\!$ means that the function $f\,\!$ dominates $g\,\!$ in some limit, see Big O notation. In this context $\Omega$ is referred to as a lower bound.
$\Omega(n)\,\!$ is the total number of prime factors of $n\,\!$ , counting prime factors with multiplicity
may refer to the Omega function, the inverse of , also known as the Lambert W function denoted .
- $\omega(x)\,\!$ , related to the Lambert W Function, is called the Wright Omega Function