Acronym  teddi, J63 
Name 
tridiminished icosahedron, ursahedron, vertex figure of sadi 
© ©  
Circumradius  sqrt[(5+sqrt(5))/8] = 0.951057 
Vertex figures  [3,5^{2}], [3^{3},5] 
General of army  (is itself convex) 
Colonel of regiment  (is itself locally convex) 
Dihedral angles 

Dual  titdi 
Confer 

External links 
As abstract polytope teddi is isomorph to targi, thereby replacing pentagons and pentagrams.
Its name ursahedron is a posterior nickname, derived from its Bowers style acronym teddi. – It furthermore expands to a whole class of related polytopes, the ursatopes.
Incidence matrix according to Dynkin symbol
xfo3oox&#xt → height(1,2) = sqrt[(3+sqrt(5))/6] = 0.934172 height(2,3) = 1/sqrt(3) = 0.577350 ({3}  pseudo f{3}  dual {3}) o..3o..  3 * *  2 1 0 0  1 2 0 0 .o.3.o.  * 3 *  0 1 2 0  0 2 1 0 ..o3..o  * * 3  0 0 2 2  0 1 2 1 +++ x.. ...  2 0 0  3 * * *  1 1 0 0 oo.3oo.&#x  1 1 0  * 3 * *  0 2 0 0 wedges .oo3.oo&#x  0 1 1  * * 6 *  0 1 1 0 ... ..x  0 0 2  * * * 3  0 0 1 1 +++ x..3o..  3 0 0  3 0 0 0  1 * * * xfo ...&#xt  2 2 1  1 2 2 0  * 3 * * ... .ox&#x  0 1 2  0 0 2 1  * * 3 * ..o3..x  0 0 3  0 0 0 3  * * * 1
© 20042018  top of page 