As far as I know for Non-Deterministic Turing Machine (NTM) there are 4 kind of branches:
- An input is accepted if there is at least one node in the tree that is an accept.
- An input is rejected if all branches are rejected, which means that it is a finite tree.
- An input is not-accepted if there are loop nodes with reject nodes.
- An input is not-accepted if there are only loop nodes.
We know that for RE-R language, our NTM must not accept some inputs.
My question is on not-accepted branches.
For a specific NTM that accepts RE-R language, is option 4 (for all nodes looping) necessary to exist?
Means that only option 3 exists without option 4.
Thanks.