Unbounded minimization
= Unbounded minimization
{title2=$\mu$}
{wiki=Mu_operator}
For a partial function $g(\mathbf x,y)$, unbounded minimization defines
$$
f(\mathbf x)=\mu y\,[g(\mathbf x,y)=0]
$$
as the least $y$ at which $g$ is zero, provided the preceding required computations are defined. If no such $y$ is found, $f(\mathbf x)$ is undefined. Closing the <primitive recursive function>[primitive recursive functions] under this operation gives the partial recursive functions.