In geometry, the icositruncated dodecadodecahedron or icosidodecatruncated icosidodecahedron is a nonconvex uniform polyhedron, indexed as U45.
Convex hull Its convex hull is a nonuniform truncated icosidodecahedron.
Cartesian coordinates Cartesian coordinates for the vertices of an icositruncated dodecadodecahedron are all the even permutations of
( ± [ 2 − 1 φ ] , ± 1 , ± [ 2 + φ ] ) , ( ± 1 , ± 1 φ 2 , ± [ 3 φ − 1 ] ) , ( ± 2 , ± 2 φ , ± 2 φ ) , ( ± 3 , ± 1 φ 2 , ± φ 2 ) , ( ± φ 2 , ± 1 , ± [ 3 φ − 2 ] ) , {\displaystyle {\begin{array}{crrlc}{\Bigl (}&\pm {\bigl [}2-{\frac {1}{\varphi }}{\bigr ]},&\pm \,1,&\pm {\bigl [}2+\varphi {\bigr ]}&{\Bigr )},\\{\Bigl (}&\pm \,1,&\pm \,{\frac {1}{\varphi ^{2}}},&\pm {\bigl [}3\varphi -1{\bigr ]}&{\Bigr )},\\{\Bigl (}&\pm \,2,&\pm \,{\frac {2}{\varphi }},&\pm \,2\varphi &{\Bigr )},\\{\Bigl (}&\pm \,3,&\pm \,{\frac {1}{\varphi ^{2}}},&\pm \,\varphi ^{2}&{\Bigr )},\\{\Bigl (}&\pm \,\varphi ^{2},&\pm \,1,&\pm {\bigl [}3\varphi -2{\bigr ]}&{\Bigr )},\end{array}}}
where φ = 1 + 5 2 {\displaystyle \varphi ={\tfrac {1+{\sqrt {5}}}{2}}} is the golden ratio.
Related polyhedra
Tridyakis icosahedron
The tridyakis icosahedron is the dual polyhedron of the icositruncated dodecadodecahedron. It has 44 vertices, 180 edges, and 120 scalene triangular faces.
See also Catalan solid Duals to convex uniform polyhedra Uniform polyhedra List of uniform polyhedra
References Wenninger, Magnus (1983), Dual Models, Cambridge University Press, ISBN 978-0-521-54325-5, MR 0730208 Photo on page 96, Dorman Luke construction and stellation pattern on page 97.
External links Weisstein, Eric W. "Icositruncated dodecadodecahedron". MathWorld.






