Golomb ruler

thingiverse

A [Golomb ruler](https://en.wikipedia.org/wiki/Golomb_ruler) is marked so that no two pairs of marks are equidistant. A Golomb ruler is considered perfect if it has as few marks as necessary, and can measure every integer distance up to its length. There's no perfect Golomb ruler with more than four marks. This one is the largest possible! It's designed for dual extrusion: changing the variable `in` to `false` will produce just the marks needed to fill in the gaps in the base model.