Acronym | addasi |
Name |
altered disnub icosahedron, compound of 20 oct (but not dasi) |
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Circumradius | 1/sqrt(2) = 0.707107 |
Inradius | 1/sqrt(6) = 0.408248 |
Vertex figure | [34] |
Dihedral angles
(at margins) |
|
Confer | |
External links |
This compound has rotational freedom. It can be obtained at φ = 0° by 2 coincident si, rotating either of the (then) coincident oct, thought of as triagular antiprisms within an ike, in opposite directions around those axes. At φ = 60° this compound again comes to be 2 coincident gissi. Inbetween there are 2 further singular positions: One, where 4 (different oriented oct coincide each, resulting in a 4-fold cover of se. The other one, when vertices coincide by pairs, resulting in a static compound of 20 oct, called dasi. (J. Bowers further uses iddasi (inner ...) for smaller values of φ, resp. oddasi (outer ...) for larger values. The reverted range at φ > 60° then gets called giddassi (great ...).)
120 | 2 2 | 3 1 || 1 ----+---------+--------++--- 2 | 120 * | 1 1 || 1 2 | * 120 | 2 0 || 1 ----+---------+--------++--- 3 | 1 2 | 120 * || 1 3 | 3 0 | * 40 || 1 ----+---------+--------++--- ♦ 6 | 6 6 | 6 2 || 20
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