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Timeline for Lattice points in cross-polytopes

Current License: CC BY-SA 3.0

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Jun 15, 2013 at 22:22 comment added Noam D. Elkies Yes I saw it, but had nothing to contribute. In large dimensions we don't know how to pack $l_1$ balls (hyperoctahedra / cross-polytopes) any more densely than $l_2$ (round/Euclidean) balls.
Jun 15, 2013 at 22:18 history edited Noam D. Elkies CC BY-SA 3.0
Much more experimental data on the pairwise coprime case; faster code
Jun 11, 2013 at 20:40 comment added Yoav Kallus @Elkies, I wonder if you saw this question from a couple of weeks ago, which also seems to be about intersection of cross polytopes with lattices: mathoverflow.net/questions/132165/…
Jun 11, 2013 at 20:32 history edited Noam D. Elkies CC BY-SA 3.0
Add proof and code
Jun 11, 2013 at 20:15 comment added Noam D. Elkies You're welcome. I'll post the gp code before long. Meanwhile, To enumerate $E \cap {\bf Z}^3$ when $(q_1,q_2,q_3) = (k,k+1,k+1)$, observe that the integer points are those with $\left|x_1\right|+\left|x_2\right|+\left|x_3\right| \leq k$ together with the $4(k+1)$ points with $x_1=0$ and $\left|x_2\right|+\left|x_3\right| = k+1$.
Jun 11, 2013 at 20:09 comment added Oleg Eroshkin Great! That is quite surprising. I assumed, that is better to look for co-prime $q_i$ for counterexamples.
Jun 11, 2013 at 20:06 vote accept Oleg Eroshkin
Jun 11, 2013 at 20:03 history answered Noam D. Elkies CC BY-SA 3.0