Geodesic
Unimodular triangulations of dilated 3-polytopes
Trudy Moskovskogo matematičeskogo obŝestva, Trudy Moskovskogo Matematicheskogo Obshchestva, Tome 74 (2013) no. 2, pp. 353-373.

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A seminal result in the theory of toric varieties, due to Knudsen, Mumford and Waterman (1973), asserts that for every lattice polytope $P$ there is a positive integer $k$ such that the dilated polytope $kP$ has a unimodular triangulation. In dimension 3, Kantor and Sarkaria (2003) have shown that $k=4$ works for every polytope. But this does not imply that every $k>4$ works as well. We here study the values of $k$ for which the result holds showing that: It contains all composite numbers. It is an additive semigroup. These two properties imply that the only values of $k$ that may not work (besides 1 and 2, which are known not to work) are $k\in\{3,5,7,11\}$. With an ad-hoc construction we show that $k=7$ and $k=11$ also work, except in this case the triangulation cannot be guaranteed to be “standard” in the boundary. All in all, the only open cases are $k=3$ and $k=5$. References: 9 entries. 
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F. Santos; G. M. Ziegler. Unimodular triangulations of dilated 3-polytopes. Trudy Moskovskogo matematičeskogo obŝestva, Trudy Moskovskogo Matematicheskogo Obshchestva, Tome 74 (2013) no. 2, pp. 353-373. http://geodesic.mathdoc.fr/item/MMO_2013_74_2_a8/

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