A colouring is polychromatic with colours if every hypergraph edge contains a vertex of every colour. This is stronger than requiring every edge to be nonmonochromatic. Under independent uniform colours, a -element edge misses at least one of three colours with probability . If each edge meets at most other edges, the edge-intersection dependency graph of events and the Lovász local lemma therefore give a polychromatic three-colouring whenever .
Take every three-element subset of a four-element vertex set as a hypergraph edge. Any three-colouring repeats a colour on two vertices. A triple containing that pair cannot contain all three colours. Thus this uniform hypergraph has no polychromatic three-colouring, although each edge meets only three other edges.
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