Acronym stappy, 5/2-pyr
Name pentagrammic pyramid,
stellated pentagonal pyramid
 
 ©
Circumradius sqrt[(5-sqrt(5))/8] = 0.587785
Vertex figures [35/2], [3,3,5/2]
General of army ov5oo&#x
Colonel of regiment (is itself locally convex)
Dihedral angles
  • between {3} and {5/2}:   arccos(sqrt[(5-2 sqrt(5))/15]) = 79.187683°
  • between {3} and {3}:   arccos(sqrt(5)/3) = 41.810315°
Confer
general pyramids:
n/d-py  
uniform relative:
gike  
External
links
wikipedia

As abstract polytope stappy is isomorph to peppy, thereby replacing the base pentagram by a pentagon.


Incidence matrix according to Dynkin symbol

ox5/2oo&#x   → height = sqrt((5+sqrt(5))/10) = 0.850651
(pt || {5/2})

tip  o.   o.    | 1 * | 4 0 | 4 0
base .o   .o    | * 5 | 1 2 | 2 1
----------------+-----+-----+----
lace oo5/2oo&#x | 1 1 | 5 * | 2 0
base .x   ..    | 0 2 | * 5 | 1 1
----------------+-----+-----+----
coat ox   ..&#x | 1 2 | 2 1 | 5 *
base .x5/2.o    | 0 5 | 0 5 | * 1

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