Chromatic Numbers of Directed Hypergraphs with No “bad” Cycles
نویسنده
چکیده
Definition 1. A directed hypergraph of uniformity k is a pair (V,E) with E ⊆ V k. The chromatic number of a directed hypergraph is the chromatic number of the associated undirected hypergraph, that is, the least number χ such that there exists a function f : V → [χ] such that for each edge e ∈ E, not all of f(e1), ..., f(ek) are equal. We’ll assume that no edge of E has any two coordinates equal to avoid annoying technical details which end up not mattering.
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تاریخ انتشار 2017