The graph formulation of the union-closed sets conjecture

@article{Bruhn2015TheGF,
  title={The graph formulation of the union-closed sets conjecture},
  author={Henning Bruhn and Pierre Charbit and Oliver Schaudt and Jan Arne Telle},
  journal={Eur. J. Comb.},
  year={2015},
  volume={43},
  pages={210-219}
}
The union-closed sets conjecture asserts that in a finite non-trivial union-closed family of sets there has to be an element that belongs to at least half the sets. We show that this is equivalent to the conjecture that in a finite non-trivial graph there are two adjacent vertices each belonging to at most half of the maximal stable sets. In this graph formulation other special cases become natural. The conjecture is trivially true for non-bipartite graphs and we show that it holds also for the… Expand
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