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So I'm lost on this one. We're given a turing machine and an initial tape. Tape is infinitely long in both ways, but all the blanks are taken out. The head is the leftmost nonblank. So the question is: If the Turing machine halts on this input, then give the output sequence; if it does not halt, then answer “does not halt” and why.

Following the turing machine it seems to halt after q1 since is the only operation.

Edit: and, if a state has only one operation such as does that mean it automatically should halt?

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  • $\begingroup$ If all the blanks are taken out, how can there be a leftmost nonblank? $\endgroup$ – Tom Zych Dec 8 '18 at 16:36
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    $\begingroup$ I'm not sure. It's what the excercise said. To be exact: "The arrow indicates the initial position of the read/write head: the leftmost nonblank symbol. If the Turing machine halts on this input, then give the output sequence; if it does not halt, then answer “does not halt”. In either case, stating your answer is sufficient; you do not have to justify your answer" $\endgroup$ – iiiiiiiiiiiiiiiiiiiiiiiiiiiiii Dec 8 '18 at 16:51
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    $\begingroup$ You’d probably better explain the notation they’re using; it doesn’t make sense to me. Everyone makes up their own Turing machine notation, there’s no standard. $\endgroup$ – Tom Zych Dec 8 '18 at 17:01
  • $\begingroup$ so the "intial tape" could be 0 | _ | 1 | _ | _ | 1 .. etc. You don't know because they took the blanks out. The turing machine: <current state>, <written state>, <move R/L>. The box is a blank. For that matter, it does not make sense to me either. I tried to search for more explanation but it as you said, everyone has a different notation $\endgroup$ – iiiiiiiiiiiiiiiiiiiiiiiiiiiiii Dec 8 '18 at 17:05
  • $\begingroup$ I’m sorry but this seems like an unanswerable question to me. The machine definition doesn’t make sense without a notation definition. The stuff about the blanks being taken out doesn’t make much sense. If you were given this for a course, I’d go back to the instructor and ask them to clarify it. $\endgroup$ – Tom Zych Dec 8 '18 at 18:17

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