Acronym ...
Name 2gike+sissid (?)
Circumradius sqrt[(5-sqrt(5))/8] = 0.587785
Vertex figure 5[5/2,6/2,6/2]
General of army ike
Colonel of regiment sissid
Confer
non-Grünbaumian master:
gike   sissid  
Grünbaumian relatives:
gacid   sissid+3gike   2sissid+gike   2sissid+4gike   3sissid+gike   4sissid+2gike  

Looks like a compound of 2 great icosahedra (gike) plus a small stellated dodecahedron (sissid), and indeed vertices coincide by five, edges coincide by three.


Incidence matrix according to Dynkin symbol

x3/2x5/2o

.   .   . | 60 |  1  2 |  2  1
----------+----+-------+------
x   .   . |  2 | 30  * |  2  0
.   x   . |  2 |  * 60 |  1  1
----------+----+-------+------
x3/2x   . |  6 |  3  3 | 20  *
.   x5/2o |  5 |  0  5 |  * 12

x3/2x5/3o

.   .   . | 60 |  1  2 |  2  1
----------+----+-------+------
x   .   . |  2 | 30  * |  2  0
.   x   . |  2 |  * 60 |  1  1
----------+----+-------+------
x3/2x   . |  6 |  3  3 | 20  *
.   x5/3o |  5 |  0  5 |  * 12

© 2004-2019
top of page