On Neighbors in Geometric Permutations
نویسندگان
چکیده
منابع مشابه
The triples of geometric permutations for families of disjoint translates
A line meeting a family of pairwise disjoint convex sets induces two permutations of the sets. This pair of permutations is called a geometric permutation. We characterize the possible triples of geometric permutations for a family of disjoint translates in the plane. Together with earlier studies of geometric permutations this provides a complete characterization of realizable geometric permut...
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A geometric permutation induced by a transversal line of a finite family F of disjoint convex sets in Rd is the order in which the transversal meets the members of the family. We prove that for each natural k, each family of k permutations is realizable (as a family of geometric permutations of some F ) in Rd for d ≥ 2k − 1, but there is a family of k permutations which is non-realizable in Rd ...
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Geometric grid classes of permutations have proven to be key in investigations of classical permutation pattern classes. By considering the representation of gridded permutations as words in a trace monoid, we prove that every geometric grid class has a growth rate which is given by the square of the largest root of the matching polynomial of a related graph. As a consequence, we characterise t...
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