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4 votes
1 answer
139 views

Longest path/snake in 2D and 3D space

Recently I was reminded of an old blogpost I wrote about packing a snake-like path into 2D space (https://www.royvanrijn.com/blog/2019/01/longest-path/). I never bothered to research this; try to find ...
Roy van Rijn's user avatar
1 vote
1 answer
299 views

Height of square pyramid stacking of spheres with different radii

What is the total height of a system consisting of 4 spheres of radius $x$ on top of which is a sphere of radius $y$? (Such that the top sphere is in the 'crevice' of the others, as seen when packing ...
Pigeon's user avatar
  • 13
1 vote
0 answers
24 views

Densest 3D packing of tori (toruses)

I have a 3D torus, say with radii $R$ (around the hole) and $r$ (thickness), where $R \gg r$. What is the densest packing, to fill a rectangular block with as many identical tori as possible? Tori ...
Tom Verhoeff's user avatar
2 votes
0 answers
124 views

Packing of consecutive cubes

Using the Ponting Square Packing, squares of size 1-49 can be packed in a 7x7 array so that the 25 interior squares are completely surrounded. Another way to look at the above squares is with the ...
Ed Pegg's user avatar
  • 21.4k
0 votes
2 answers
841 views

Volume of air in the box (packing problem)

Suppose I have a box with dimensions $L \times W \times H$. What is the volume of air in the box, if I pack balls with radii $r$? With increase of radius, does volume of air decrease?
eMathHelp's user avatar
  • 2,319
3 votes
0 answers
101 views

Orthogonally packing consecutive integer cubes 1x1x1 -nxnxn inside the smallest integer cube.

For small n, the problem of orthogonally packing consecutively sized integer cubes 1x1x1 - nxnxn inside the smallest integer cube CxCxC is trivial. By inspection, the sizes of two largest cubes n and ...
Brian Trial's user avatar
3 votes
1 answer
755 views

Prove that a triangulated hexagon will have an equal number of double-triangle tiles in each direction.

Good afternoon! I got the problem below from my tutor, which should help with thinking about problems. A regular hexagon is drawn on isometric paper, with each triangle having side length 1. Two of ...
mathmatics's user avatar
2 votes
2 answers
2k views

Maximal number of cubes in a given pyramid

I have a pyramid whose base is a square of side length $a=120$, and whose height is also $a=120$. The projection of the summit of the pyramid on the square basis coincides with the center of the ...
Alphonse's user avatar
  • 6,362
0 votes
2 answers
153 views

Unusual 3D Packing Problem

I made up this interesting problem playing with wire sculptures: If I have a $10 \times 10 \times 10$ clear box and inside I can put wireframe unit cubes, what's the maximum number of unit edges (or ...
qwr's user avatar
  • 10.8k
1 vote
0 answers
152 views

3D Space Covering-Problem

Given a finite amount of "slots" in 3D space, e.g. $$S = [(1,2,3),(1,3,3),(1,4,3),(1,3,4)] \in \mathbb{N}^3.$$ I'm trying to find an efficient algorithm to determine a minimal set of (rectangular) ...
vincent's user avatar
  • 31