**Authors:** Julian A.D. Allagan, Kenneth L. Jones

**Keywords:** Catalan numbers, Chromatic spectrum, Mixed hypergraph coloring, Stirling numbers.

### Abstract

An {\it $H$-WORM} coloring of a simple graph $G$ is the coloring of the vertices of $G$ such that no copy of $H\subseteq G$ is monochrome or rainbow. In a recently published article by one of the authors \cite{All1}, it was claimed that the number of $r$-partitions in a $K_s$-WORM coloring of $K_n$ is $ \zeta_r=\stirr{n}{r}$, where $\stirr{n}{r}$ denotes the Stirling number of the second kind, for all $3\le r\le s < n$. We found that $ \displaystyle \zeta_r = \stirr{n}{r}$ if and only if ${\lceil \frac{n+3}{2} \rceil}

Elizabeth City State University

Elizabeth City, North Carolina, U.S.A

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