Acronym epro, J21
Name elongated pentagonal rotunda
VRML 
 ⭳ ©
Vertex figure [(3,5)2], [3,5,42], [42,10]
General of army (is itself convex)
Colonel of regiment (is itself locally convex)
Dihedral angles
  • between {3} and {4}:   arccos(-sqrt[(10+2 sqrt(5))/15]) = 169.187683°
  • between {5} and {4}:   arccos(-2/sqrt(5)) = 153.434949°
  • between {4} and {4}:   144°
  • between {3} and {5}:   arccos(-sqrt[(5+2 sqrt(5))/15]) = 142.622632°
  • between {4} and {10}:   90°
Face vector 30, 55, 27
Confer
uniform relative:
id   dip  
related Johnson solids:
pero   epobro   epgybro  
general polytopal classes:
Johnson solids  
External
links 		wikipedia   polytopewiki   mathworld   quickfur  

Incidence matrix according to Dynkin symbol

xoxx5ofxx&#xt   → height(1,2) = sqrt[(5-sqrt(5))/10] = 0.525731
                  height(2,3) = sqrt[(5+sqrt(5))/10] = 0.850651
                  height(3,4) = 1
({5} || pseudo dual f-{5} || pseudo {10} || {10})

o...5o...     | 5 *  *  * | 2  2  0 0 0  0 0 0 | 1 2 1 0 0 0 0
.o..5.o..     | * 5  *  * | 0  2  2 0 0  0 0 0 | 0 1 2 1 0 0 0
..o.5..o.     | * * 10  * | 0  0  1 1 1  1 0 0 | 0 0 1 1 1 1 0
...o5...o     | * *  * 10 | 0  0  0 0 0  1 1 1 | 0 0 0 0 1 1 1
--------------+-----------+--------------------+--------------
x... ....     | 2 0  0  0 | 5  *  * * *  * * * | 1 1 0 0 0 0 0
oo..5oo..&#x  | 1 1  0  0 | * 10  * * *  * * * | 0 1 1 0 0 0 0
.oo.5.oo.&#x  | 0 1  1  0 | *  * 10 * *  * * * | 0 0 1 1 0 0 0
..x. ....     | 0 0  2  0 | *  *  * 5 *  * * * | 0 0 0 1 1 0 0
.... ..x.     | 0 0  2  0 | *  *  * * 5  * * * | 0 0 1 0 0 1 0
..oo5..oo&#x  | 0 0  1  1 | *  *  * * * 10 * * | 0 0 0 0 1 1 0
...x ....     | 0 0  0  2 | *  *  * * *  * 5 * | 0 0 0 0 1 0 1
.... ...x     | 0 0  0  2 | *  *  * * *  * * 5 | 0 0 0 0 0 1 1
--------------+-----------+--------------------+--------------
x...5o...     | 5 0  0  0 | 5  0  0 0 0  0 0 0 | 1 * * * * * *
xo.. ....&#x  | 2 1  0  0 | 1  2  0 0 0  0 0 0 | * 5 * * * * *
.... ofx.&#xt | 1 2  2  0 | 0  2  2 0 1  0 0 0 | * * 5 * * * *
.ox. ....&#x  | 0 1  2  0 | 0  0  2 1 0  0 0 0 | * * * 5 * * *
..xx ....&#x  | 0 0  2  2 | 0  0  0 1 0  2 1 0 | * * * * 5 * *
.... ..xx&#x  | 0 0  2  2 | 0  0  0 0 1  2 0 1 | * * * * * 5 *
...x5...x     | 0 0  0 10 | 0  0  0 0 0  0 5 5 | * * * * * * 1

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