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Can someone please tell me the difference between Non re and CoRE languages with an example?

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  • $\begingroup$ It seems that the definitions answer your question. $\endgroup$ – Raphael Dec 8 '17 at 9:08
  • $\begingroup$ I know what is co-re. I am not sure about non r.e $\endgroup$ – Sagar P Dec 8 '17 at 9:15
  • $\begingroup$ If you know what "r.e." is, it should be clear what "not r.e.". They are related like "blue" and "not blue". $\endgroup$ – Raphael Dec 8 '17 at 10:10
  • $\begingroup$ R.E means halts on "yes" cases and we can't say anything about "no" cases. Co R.E means halts on "no" cases and we can't say anything about "yes" cases. Now what is non r.e ? Also, Not R.E and Non R.E are different right? $\endgroup$ – Sagar P Dec 8 '17 at 10:22
  • $\begingroup$ A set is non r.e. if it isn't r.e. That's the same thing as the set being not r.e. $\endgroup$ – Yuval Filmus Dec 8 '17 at 12:54