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A comment on A regular expression to check for prime numbers. Parent comment

Re:A regular expression to check for prime numbers by Tainnor on Wednesday June 21, 2023 @06:28AM (#36416745)
Via the context-free pumping lemma, you can even prove that prime numbers don't form a context-free language either.
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Re:A regular expression to check for prime numbers by taejo on Wednesday June 21, 2023 @08:07AM (#36417411)
And via Parikh's theorem, with a one-symbol alphabet, regular and context-free languages are the same.
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