Existence of words over a three-letter alphabet not containing squares with errors of replacing

The paper concerns some problems related to the existence of periodic structures in words from formal languages. Squares, i.e. fragments of the form $xx$, where $x$ is some word, and $\Delta$-squares, i.e. fragments of the form $xy$, where the word $x$ is different from the word $y$ by not more than $\Delta$ letters, are considered as periodic structures. We show the existence of arbitrarily long words over three-letter alphabet not containing $\Delta$-squares with the period exceeding $\Delta$. In particular, such words are constructed for all possible values $\Delta$.