The Quantifier Semigroup for Bipartite Graphs

نویسنده

  • Leonard J. Schulman
چکیده

In a bipartite graph there are two widely encountered monotone mappings from subsets of one side of the graph to subsets of the other side: one corresponds to the quantifier “there exists a neighbor in the subset” and the other to the quantifier “all neighbors are in the subset.” These mappings generate a partially ordered semigroup which we characterize in terms of “run-unimodal” words.

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عنوان ژورنال:
  • Electr. J. Comb.

دوره 18  شماره 

صفحات  -

تاریخ انتشار 2011