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{\bf Manfred Walter}
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{\bf Some Results on Chromatic Polynomials of Hypergraphs}
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In this paper, chromatic polynomials of (non-uniform) hypercycles,
unicyclic hypergraphs, hypercacti and sunflower hypergraphs are
presented.  The formulae generalize known results for $r$-uniform
hypergraphs due to Allagan, Borowiecki/{\L}azuka, Dohmen and Tomescu.
 
Furthermore, it is shown that the class of (non-uniform) hypertrees
with $m$ edges, where $m_r$ edges have size $r$, $r\geq 2$, is
chromatically closed if and only if $m\leq4$, $m_2\geq m-1$.

\bye