Fixing a Square
Imagine a toy like that shown in the diagram.
You can create an equilateral triangle using three of the rods.
You could also create a square, but it will be so unstable that even a small amount of pressure will deform it.
You want to create a stable, fixed square.
How is this possible, using any number of parts?
The easiest way is by creating a square pyramid.
Doing this in a plane requires 23 parts.
It involves creating a diagonal square base with width Root(2), adding height 1 rods, and fixing with a Root(3) hypotenuse.
