Logspace transducer
= Logspace transducer
A deterministic <Turing machine> with read-only <input>, $O(\log(n+2))$ work space, and successive write-only output whose contents it cannot inspect. A transducer for a total function halts on every <input>. It has a <polynomial> number of internal <Turing machine configurations>, so a halting run emits only a <polynomial> number of symbols. The unreadable output position does not affect subsequent transitions.