Trees as semilattices

نویسندگان

  • Leonid Libkin
  • Vladimir Gurvich
چکیده

We study semilattices whose diagrams are trees. First, we characterize them as semilattices whose convex subsemilattices form a convex geometry, or, equivalently, the closure induced by convex subsemilattices is antiexchange. Then we give lattice theoretic and two graph theoretic characterizations of atomistic semilattices with tree diagrams.

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عنوان ژورنال:
  • Discrete Mathematics

دوره 145  شماره 

صفحات  -

تاریخ انتشار 1995