I am currently studying the pumping lemma for regular languages and I am trying to come up with an example where even if the language can be pumped it is not regular. Which condition of the lemma should be broken such that I can find a language like that?
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Gilles 'SO- stop being evil'
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1What do you mean "which condition should be broken"? The idea is that all the conditions do hold, yet still the language is not regular. – Shaull Sep 28 '13 at 11:26
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1There's a counter-example in Wikipedia, but it doesn't give any intuition as to how where this example comes from. – Gilles 'SO- stop being evil' Sep 28 '13 at 12:00
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1@Gilles nice.. i did not know of it either, so thanks :). And you should make this to an answer. – Subhayan Sep 28 '13 at 12:30
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@user1704040 if you relax any of the conditions, the lemma won't hold, try to relax the three one by one, and see there's always some language 'fits' into it. – Subhayan Sep 28 '13 at 12:32
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See the related Languages that satisfy the pumping lemma but aren't regular?. The remark of @Shauli was to the point here however. – Hendrik Jan Sep 28 '13 at 12:55