Labeled posets are universal

نویسنده

  • Erkko Lehtonen
چکیده

Partially ordered sets labeled with k labels (k-posets) and their homomorphisms are examined. The homomorphicity order of k-posets is shown to be a distributive lattice. Homomorphicity orders of k-posets and k-lattices are shown to be universal in the sense that every countable poset can be embedded into them. Labeled posets are represented by directed graphs, and a categorical isomorphism between k-posets and their digraph representations is established.

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عنوان ژورنال:
  • Eur. J. Comb.

دوره 29  شماره 

صفحات  -

تاریخ انتشار 2008