Sum of squares

thingiverse

How much is 1+2^2+3^2+...+n^2 ? Well, that what this puzzle is about. If you have 3 pieces like that, you can build almost a cube, so it's about n^3/3. But if you have 6 pieces, you can really fit them into a cuboid, of sizes n, n+1 and 2n+1 so you get that 1+2^2+3^2+...+n^2=n(n+1)(2n+1)/6I have created it with OpenScad cloudhttps://openscad.cloud/openscad/Another version cutting wood with geogebra: https://www.geogebra.org/m/ChWf5vbe#material/qb8JhgPm