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Joseph O'Rourke
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Can we find lattice polyhedra with faces of area 1,2,3,...?

I asked this question two months ago on MSE, where it earned the rare Tumbleweed badge for garnering zero votes, zero answers, and 25 views over 61 days. Perhaps justifiably so! Here I repeat it with slight improvements.


Let $P$ be a polyhedron, all of whose vertices are at points of $\mathbb{Z}^3$, all of whose edges are parallel to an axis, with every face simply connected, and the surface topologically a sphere. Let $A(P)$ be the *area sequence*, the sorted list of areas of $P$'s faces. For example:
           
Using regular expression notation, this sequence can be written as $1^4 2^2 3^2$.

In analogy with golygons, I wondered if there is a $P$ with $A(P)= 1^1 2^1 3^1 4^1 5^1 \cdots$. I don't think so, i.e., I conjecture there are no golyhedra. Q1. Can anyone prove or disprove this?

Easier is to achieve $A(P)= 1^+ 2^+ 3^+ \cdots$, where $a^+$ means one or more $a$'s. For example, this polyhedron achieves $1^+ 2^+ 3^+ 4^+ 5^+ 6^+$:
      OrthoPolyhedronTwisted6
Q2. But can $A(P)= 1^n 2^n 3^n \cdots$ be achieved, for some $n$? The above example is in some sense close, with $A(P) = \cdots 4^4 5^4 6^4 \cdots$, but end effects destroy the regularity.

The broadest question is: Q3. Which sequences $A(P)$ are achievable? Can they be characterized? Or at least constrained?

Joseph O'Rourke
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