Corpus ID: 102488175

Non-intersecting Ryser hypergraphs

  title={Non-intersecting Ryser hypergraphs},
  author={A. Bishnoi and V. Pepe},
  journal={arXiv: Combinatorics},
A famous conjecture of Ryser states that every $r$-partite hypergraph has vertex cover number at most $r - 1$ times the matching number. In recent years, hypergraphs meeting this conjectured bound, known as $r$-Ryser hypergraphs, have been studied extensively. It was recently proved by Haxell, Narins and Szab\'{o} that all $3$-Ryser hypergraphs with matching number $\nu > 1$ are essentially obtained by taking $\nu$ disjoint copies of intersecting $3$-Ryser hypergraphs. Abu-Khazneh showed that… Expand

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