# Tag Info

Trying to answer the many questions you have here to the best of my ability: what is R(M)? They say it is representation of turing machine but what is it exactly? Is it tuples of turing machine? It is some representation of some Turing Machine $M$. The exact format of the representation is not important for this proof, just that it unambiguously specifies ...
This statement is incorrect. If $\overline{A_{TM}}$ is co-recognizable, then we have a TM that recognizes the set of words not accepted by some TM $M$. The fact that $\overline{A_{TM}}$ is co-recognizable means that there is a TM $T$ that recognizes all words not in $\overline{A_{TM}}$. Equivalently, $T$ recognizes all words in \$\overline{\overline{A_{TM}}}...