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arXiv · 2211.03150

New Bounds for the Integer Carath\'{e}odory Rank

Iskander Aliev·Martin Henk·Mark Hogan·Stefan Kuhlmann·Timm Oertel
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Abstract

Given a rational pointed $n$-dimensional cone $C$, we study the integer Carath\'{e}odory rank $\operatorname{CR}(C)$ and its asymptotic form $\operatorname{CR^{\rm a}}(C)$, where we consider ``most'' integer vectors in the cone. The main result significantly improves the previously known upper bound for $\operatorname{CR^{\rm a}}(C)$. We also study bounds on $\operatorname{CR}(C)$ in terms of $\Delta$, the maximal absolute $n\times n$ minor of the matrix given in an integral polyhedral representation of $C$. If $\Delta\in\lbrace 1,2\rbrace$, we show $\operatorname{CR}(C) = n$, and prove upper bounds for simplicial cones, improving the best known upper bound on $\operatorname{CR}(C)$ for $\Delta\leq n$.

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Iskander Aliev, Martin Henk, Mark Hogan, Stefan Kuhlmann, Timm Oertel. 2022-11-06. New Bounds for the Integer Carath\'{e}odory Rank. https://arxiv.org/abs/2211.03150

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