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    List colorings of kk-partite kk-graphs

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    A kk-uniform hypergraph (or kk-graph) H=(V,E)H = (V, E) is kk-partite if VV can be partitioned into kk sets V1,…,VkV_1, \ldots, V_k such that each edge in EE contains precisely one vertex from each ViV_i. In this note, we consider list colorings for such hypergraphs. We show that for any Ο΅>0\epsilon > 0 if each vertex v∈V(H)v \in V(H) is assigned a list of size ∣L(v)∣β‰₯((kβˆ’1+Ο΅)Ξ”/log⁑Δ)1/(kβˆ’1)|L(v)| \geq \left((k-1+\epsilon)\Delta/\log \Delta\right)^{1/(k-1)}, then HH admits a proper LL-coloring, provided Ξ”\Delta is sufficiently large. Up to a constant factor, this matches the bound on the chromatic number of simple kk-graphs shown by Frieze and Mubayi, and that on the list chromatic number of triangle free kk-graphs shown by Li and Postle. Our results hold in the more general setting of "color-degree" as has been considered for graphs. Furthermore, we establish a number of asymmetric statements matching results of Alon, Cambie, and Kang for bipartite graphs.Comment: 12 page
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