Re: Orange stacks

On Mon, 14 Jul 2025 11:54:06 -0000 (UTC), Richard Tobin wrote:

But - hard though it may seem to believe - no!

Oh!... I do find that hard to believe. Here's what I see (think I see).

If I use the centres as defining points:

Then one shape (from the square pyramid) has a square top and bottom. It
looks to me like a truncated octahedron.

The second shape (from the triangular pyramid) is based exclusively on
equilateral triangles and is entirely regular - is is what I think of when
I think of a diamond crystal lattice.

In my mind, to be the same, the rows in the base of the square-based
pyramids base would need to be offset left and right, such that the
distance between any three adjacent spheres is minimized. It is no longer
square-based, but is a triangular-based pyramid standing in a square box.

I can see I'm going to have to buy some golf balls, or table tennis balls.

--
David Entwistle