Repeated Word List

Repeated Word List (short RepWL) is a decider. It works by splitting the tape contents into blocks ("words") of a given length $l$. Consecutive blocks grouped into powers. If there are more consecutive repeating blocks than a predefined repeat threshhold $T$, the exponent is given as $T+$. Consecutive blocks with no $+$ in their exponent are called constant blocks. When the TM head is facing a constant block, the TM is simulated until it either leaves the constant block, halts, or exceeds a predefined step limit $B$. Once the TM has left the constant block, identical contiguous blocks are regrouped into powers. If the TM head is facing a group of blocks with a $+$ in its exponent, the block directly faced by the TM head is separated from the group and the simulation splits into two branches: One where the original groups multiplicity is reduced to $T-1$ and one where it stays at $T+$.