Hi try to figure out how to annotate a color swatch, consisting out of n RGB values and tried to outline it below, does this make any sense? Should RGB colors generally be described as vectors?
Let $S$ to be a set (color-swatch) containing a finite set of discrete RGB-colors $c_a$ of size $n_S$. \begin{equation} (c_a \in S \mid 1 \leq a \leq n_s) \end{equation}
Each RGB-Color $c_a$ , in turn consists out of an integer triplet of values $c_a = (v_r,v_g,v_b)$ corresponding to the red, green and blue color channel: \begin{equation} c_a = \{ v_i \in \mathbb{N^3} \mid 0 \leq i \leq 255 \} \end{equation}
Our database $D$ of size $n_D$, consists also of a finite set of discrete color-swatches $D = \{\ S_{1D} ... S_{nD} \}\ $. Let a target color swatch $S_t$ to be compared to has the attribute $S_t \notin D$.