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'Chomsky normal form'
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| Title of object: |
Chomsky normal form |
| Canonical Name: |
ChomskyNormalForm |
| Type: |
Definition |
| Created on: |
2006-10-28 21:04:21 |
| Modified on: |
2006-10-28 22:25:28 |
| Classification: |
msc:68Q45, msc:68Q42 |
Preamble:
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Content:
A grammar is said to be of \emph{Chomsky normal form} if every production
has either the form
\[A \to BC \]
where $A,B,C$ are non-terminal symbols or the form
\[A \to a \]
where $A$ is a terminal symbol and $a$ is a normal symbol.
Grammars of this sort are context-free, hence they describe context-free
languages. Moreover, given any context-free language, there exists a
Chomsky normal form grammar which describes it. |
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