Looping variable of a regular grammar
= Looping variable of a regular grammar
A variable $A$ is looping when $A\Rightarrow^*wA$ for some terminal word $w$ through a nonempty derivation.
= Looping variable of a regular grammar
A variable $A$ is looping when $A\Rightarrow^*wA$ for some terminal word $w$ through a nonempty derivation.