Self-similar hex-sums of squares (Q976297)

\textit{A. van der Poorten, K. Thomsen} and \textit{M. Wiebe} [Math. Intell. 29, No. 2, 39--41 (2007; Zbl 1158.11313)] considered so called self-similar sums of squares. This was connected with the norms of Gaussian integers. Analogously, using the norms of Eisenstein integers of the form \(a\pm b\omega\), where \(\omega=(-1+\sqrt{-3})/2\), the author studies so called self-similar hex-sums of squares.