Avoiding Abelian and Additive Powers in Rich Words
摘要
This paper concerns the avoidability of abelian and additive powers in infinite rich words. In particular, we construct an infinite additive 5-power-free rich word over \(\{\texttt {0},\texttt {1}\}\) and an infinite additive 4-power-free rich word over \(\{\texttt {0},\texttt {1},\texttt {2}\}\) . The alphabet sizes are as small as possible in both cases, even for abelian powers.