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Given a context-free grammar G. Is it decidable, if the language $L(G)$, which is generated by G, contains a palindrome?

My suggestion is, that it is undecidable, but I do not have an idea for a formal prove. Any hints?

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    $\begingroup$ It can be proved undecidable using the fact that we cannot decide whether two CF languages have a nonempty intersection. Or, whether the Post Correspondence Problem has a solution; the latter will lead to undecidability even for the subfamily of linear languages: Palindromes and linear grammars $\endgroup$ Commented Dec 2, 2017 at 20:11

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