Abstract
In this paper we investigate the number of integer points lying in dilations of lattice path matroid polytopes. We give a characterization of such points as polygonal paths in the diagram of the lattice path matroid. Furthermore, we prove that lattice path matroid polytopes are affinely equivalent to a family of distributive polytopes. As applications we obtain two new infinite families of matroids verifying a conjecture of De Loera et. al. and present an explicit formula of the Ehrhart polynomial for one of them.
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Acknowledgements
The first author was partially supported by ANR Grants GATO ANR-16-CE40-0009-01 and CAPPS ANR-17-CE40-0018. The second author was supported by the Israel Science Foundation Grant No. 1452/15 and the European Research Council H2020 programme Grant No. 678765. The last two authors were partially supported by ECOS Nord Project M13M01.
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Knauer, K., Martínez-Sandoval, L. & Ramírez Alfonsín, J.L. On Lattice Path Matroid Polytopes: Integer Points and Ehrhart Polynomial. Discrete Comput Geom 60, 698–719 (2018). https://doi.org/10.1007/s00454-018-9965-4
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DOI: https://doi.org/10.1007/s00454-018-9965-4