Sentential Form

languages

Definition

Sentential Form

Let $G=⟨N,T,P,S⟩$ be a grammar. A word $w\in N\cup T$ is called sentential form if the production rule $S\Rightarrow w$ exists.

The set of all sentential forms over $G$ that can be produced within $n$ steps is given by:

$$SF(G,n)=\{w\in (N\cup T{)}^{\ast }\mid S{\Rightarrow }^{n}w\}$$