FOCS
2006
IEEE
13 years 10 months ago
2006
IEEE
We show that 2-tag systems efficiently simulate Turing machines. As a corollary we find that the small universal Turing machines of Rogozhin, Minsky and others simulate Turing ma...
FCT
2009
Springer
13 years 11 months ago
2009
Springer
We give small universal Turing machines with state-symbol pairs of (6, 2), (3, 3) and (2, 4). These machines are weakly universal, which means that they have an infinitely repeate...