Abstract
Nondeterministic one-wayk-head writing finite automata are investigated. It is shown that 3-head automata with one read-write head followed by two read-only heads are as powerful as any multihead automaton. Furthermore, a new way to detect a coincidence of heads is introduced, which has as a consequence that it makes no difference, whether the heads make stationary moves ore-moves.
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This research was done while the author visited the Department of Mathematics, University of California at Santa Barbara.
The work was supported in part by the National Science Foundation under Grant MCS 77-11360 and by the German Academic Exchange Service under NATO Research Grant 430/402/777/9.
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Brandenburg, FJ. Three write heads are as good ask . Math. Systems Theory 14, 1–12 (1981). https://doi.org/10.1007/BF01752387
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DOI: https://doi.org/10.1007/BF01752387