Sync bi-counter
Sync bi-counter is an informal class of Turing machines. A typical Turing machine in this class has the following behavior:
- It has two counters on the tape, and the lowest digit of both counters are adjacent.
- In each round, both of the two counters are increased by one, and they count in the same base. Both counters count to the same number after each round (i.e. they are synchronized).