The density Turán problem for some 3-uniform unihypercyclic linear hypergraphs An efficient testing algorithm
نویسندگان
چکیده
Let H = (V, E) be a 3-uniform linear hypergraph with one hypercycle C3. We consider a blow-up hypergraph B[H]. We are interested in the following problem. We have to decide whether there exists a blow-up hypergraph B[H] of the hypergraph H, with hyperedge densities satisfying special conditions, such that the hypergraph H appears in a blow-up hypergraph as a transversal. We present an efficient algorithm to decide whether a given set of hyperedge densities ensures the existence of a 3-uniform linear hypergraph H with hypercycle C3 in the blow-up hypergraph B[H]. Moreover, we state some relations between roots of the multivariate matching polynomial and the inhomogeneous density Turán problem.
منابع مشابه
Turán Problems on Non-Uniform Hypergraphs
A non-uniform hypergraph H = (V,E) consists of a vertex set V and an edge set E ⊆ 2V ; the edges in E are not required to all have the same cardinality. The set of all cardinalities of edges in H is denoted by R(H), the set of edge types. For a fixed hypergraph H, the Turán density π(H) is defined to be limn→∞maxGn hn(Gn), where the maximum is taken over all H-free hypergraphs Gn on n vertices ...
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