In fact, both representations are equivalent(the one that has the option to
stay in the same cell and the one that doesn't).
In our case, you will have to use another state to emulate that behaviour.

On Fri, May 9, 2008 at 11:42 PM, James Gray <james@[...].net> 
wrote:

>  On May 9, 2008, at 11:23 PM, Chiyuan Zhang wrote:
> 
>   Does it mean the tape head move action can only be [RL] ? Is there an
> > instruction for not moving the head?
> >
> 
>  Correct, the tape moves with each instruction.
> 
>  James Edward Gray II
> 
> 


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