Dismantlable Lattices in the Mirror
نویسندگان
چکیده
We investigate properties which hold for both the lattice of a binary relation and for its ’mirror lattice’, which is the lattice of the complement relation. We first prove that the relations whose lattice is dismantlable correspond to the class of chordal bipartite graphs; we provide algorithmic tools to find a doubly irreducible element in such a lattice. We go on to show that a lattice is dismantlable and its mirror lattice is also dismantlable if and only if both these lattices are planar.
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