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arXiv · 1002.0536

Enumerating and identifying semiperfect colorings of symmetrical patterns

Rene P. Felix·Manuel Joseph C. Loquias
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Abstract

If $G$ is the symmetry group of an uncolored pattern then a coloring of the pattern is semiperfect if the associated color group $H$ is a subgroup of $G$ of index 2. We give results on how to identify and enumerate all inequivalent semiperfect colorings of certain patterns. This is achieved by treating a coloring as a partition $\{hJ_iY_i:i\in I,h\in H\}$ of $G$, where $H$ is a subgroup of index 2 in $G$, $J_i\leq H$ for $i\in I$, and $Y=\cup_{i\in I}{Y_i}$ is a complete set of right coset representatives of $H$ in $G$. We also give a one-to-one correspondence between inequivalent semiperfect colorings whose associated color groups are conjugate subgroups with respect to the normalizer of $G$ in the group of isometries of $\mathbf{R}^n$.

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Rene P. Felix, Manuel Joseph C. Loquias. 2010-02-02. Enumerating and identifying semiperfect colorings of symmetrical patterns. https://doi.org/10.1524/zkri.2008.0053

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