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arXiv · 2006.15730

Conditions for a bigraph to be super-cyclic

Alexandr Kostochka·Mikhail Lavrov·Ruth Luo·Dara Zirlin
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Abstract

A hypergraph $\mathcal H$ is super-pancyclic if for each $A \subseteq V(\mathcal H)$ with $|A| \geq 3$, $\mathcal H$ contains a Berge cycle with base vertex set $A$. We present two natural necessary conditions for a hypergraph to be super-pancyclic, and show that in several classes of hypergraphs these necessary conditions are also sufficient for this. In particular, they are sufficient for every hypergraph $\mathcal H$ with $ \delta(\mathcal H)\geq \max\{|V(\mathcal H)|, \frac{|E(\mathcal H)|+10}{4}\}$. We also consider super-cyclic bipartite graphs: those are $(X,Y)$-bigraphs $G$ such that for each $A \subseteq X$ with $|A| \geq 3$, $G$ has a cycle $C_A$ such that $V(C_A)\cap X=A$. Such graphs are incidence graphs of super-pancyclic hypergraphs, and our proofs use the language of such graphs.

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Alexandr Kostochka, Mikhail Lavrov, Ruth Luo, Dara Zirlin. 2020-06-28. Conditions for a bigraph to be super-cyclic. https://arxiv.org/abs/2006.15730

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