Can You Minimize Production Rules in Chomsky Normal Form?

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SUMMARY

The discussion focuses on proving that any context-free grammar (CFG) without λ productions or unit productions can be transformed into an equivalent grammar in Chomsky Normal Form (CNF) with a limited number of production rules. Specifically, it establishes that the number of production rules in CNF will not exceed (k − 1)|P| + |T|, where k is the maximum number of symbols on the right side of any production in P, |P| is the number of productions, and |T| is the number of terminal symbols. The participants express the challenge of finding a proof that minimizes production rules in CNF, noting the lack of similar proofs available online.

PREREQUISITES
  • Understanding of context-free grammars (CFGs)
  • Familiarity with Chomsky Normal Form (CNF)
  • Knowledge of production rules and their structure
  • Basic concepts of formal language theory
NEXT STEPS
  • Research the process of converting CFGs to Chomsky Normal Form
  • Study the implications of λ productions and unit productions in CFGs
  • Explore inductive and constructive proof techniques in formal language theory
  • Examine existing proofs related to minimizing production rules in CNF
USEFUL FOR

Students of formal language theory, computer science researchers, and educators looking to deepen their understanding of context-free grammars and Chomsky Normal Form.

twoski
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Homework Statement



Grammar 'G' is any context-free grammar without any λ productions or unit productions. Let k be the max number of symbols on the right side of any production in P. Prove that there's an equivalent grammar in Chomsky Normal Form with no more than (k − 1)|P| + |T| production rules.

The Attempt at a Solution



There isn't a single similar proof to this anywhere on the internet. There are a lot of basic proofs like proving any CFG can be converted to CNF but nothing this involved.

None of the proofs in my textbook involve minimizing production rules either. Productions in CNF can only be like A -> BC or A- > a, so this would be a factor. I don't know what else to do, should this proof be constructive or inductive?
 
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