FOCS
2006
IEEE
14 years 6 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
14 years 7 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...