On cardinalities of $k$-abelian equivalence classes

Juhani Karhumäki, Svetlana Puzynina, Michaël Rao +1

Two words $u$ and $v$ are $k$-abelian equivalent if, for each word $x$ of length at most $k$, $x$ occurs equally many times as a factor in both $u$ and $v$. The notion of $k$-abeli…