The coordinates of this family of polyhedra were found by Christian Lawson-Perfect and Michael White (see [url=https://aperiodical.com/2013/10/an-enneahedron-for-herschel/]this Aperiodical article[/url] and [url=https://www.youtube.com/watch?v=3X2aQIMx5bs]this Numberphile video[/url]). The polyhedra have nine faces and 11 vertices. It has one degree of freedom; use the slider for the parameter [i]a[/i] to see the various polyhedra. [br][br]What's special about this family? The net of these polyhedra is the [i]Herschel graph[/i]: the smallest non-Hamiltonian polyhedral graph.