Two universal Turing machines with at most two left instructions. (Deux machines de Turing universelles à au plus deux instructions gauches.) (French) Zbl 0834.68025

Summary: A universal Turing machine is constructed on alphabet \(\{0,1\}\), the program of which contains precisely two instructions involving left moves. Another one is constructed on \(\{0,1,2\}\) with a single instruction involving a left move.


68Q05 Models of computation (Turing machines, etc.) (MSC2010)
03D10 Turing machines and related notions