Octagrammic-enneagrammic duoprism

The octagrammic-enneagrammic duoprism, also known as stostedip or the 8/3-9/2 duoprism, is a uniform duoprism that consists of 9 octagrammic prisms and 8 enneagrammic prisms, with 2 of each meeting at each vertex.

The name can also refer to the octagrammic-great enneagrammic duoprism.

Coordinates
The vertex coordinates of an octagrammic-enneagrammic duoprism, centered at the origin and with edge length 2sin(2π/9), are given by:


 * (±sin(2π/9)($\sqrt{2–√2}$–1), ±sin(2π/9), 1, 0),
 * (±sin(2π/9)($\sqrt{2}$–1), ±sin(2π/9), cos(2π/9), ±sin(2π/9)),
 * (±sin(2π/9)($\sqrt{2}$–1), ±sin(2π/9), cos(4π/9), ±sin(4π/9)),
 * (±sin(2π/9)($\sqrt{2}$–1), ±sin(2π/9), –1/2, ±$\sqrt{2}$/2),
 * (±sin(2π/9)($\sqrt{2}$–1), ±sin(2π/9), cos(8π/9), ±sin(8π/9)),
 * (±sin(2π/9), ±sin(2π/9)($\sqrt{3}$–1), 1, 0),
 * (±sin(2π/9), ±sin(2π/9)($\sqrt{2}$–1), cos(2π/9), ±sin(2π/9)),
 * (±sin(2π/9), ±sin(2π/9)($\sqrt{2}$–1), cos(4π/9), ±sin(4π/9)),
 * (±sin(2π/9), ±sin(2π/9)($\sqrt{2}$–1), –1/2, ±$\sqrt{2}$/2),
 * (±sin(2π/9), ±sin(2π/9)($\sqrt{2}$–1), cos(8π/9), ±sin(8π/9)).