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On tropical Kleene star matrices and alcoved polytopes

María Jesús de la Puente (2013)

Kybernetika

In this paper we give a short, elementary proof of a known result in tropical mathematics, by which the convexity of the column span of a zero-diagonal real matrix A is characterized by A being a Kleene star. We give applications to alcoved polytopes, using normal idempotent matrices (which form a subclass of Kleene stars). For a normal matrix we define a norm and show that this is the radius of a hyperplane section of its tropical span.

Rank 1 forms, closed zones and laminae

Michel Deza, Viatcheslav Grishukhin (2002)

Journal de théorie des nombres de Bordeaux

For a given lattice, we establish an equivalence between closed zones for the corresponding Voronoï polytope, suitable hyperplane sections of the corresponding Delaunay partition, and rank 1 quadratic forms which are extreme rays for the corresponding L -type domain.

Six lonely runners.

Bohman, Tom, Holzman, Ron, Kleitman, Dan (2001)

The Electronic Journal of Combinatorics [electronic only]

Substitutions, abstract number systems and the space filling property

Clemens Fuchs, Robert Tijdeman (2006)

Annales de l’institut Fourier

In this paper we study multi-dimensional words generated by fixed points of substitutions by projecting the integer points on the corresponding broken halfline. We show for a large class of substitutions that the resulting word is the restriction of a linear function modulo 1 and that it can be decided whether the resulting word is space filling or not. The proof uses lattices and the abstract number system associated with the substitution.

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