Acronym peppy, 5pyr, J2
Name pentagonal pyramid
 
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Circumradius sqrt[(5+sqrt(5))/8] = 0.951057
Vertex figures [35], [3,3,5]
General of army (is itself convex)
Colonel of regiment (is itself locally convex)
Dual (topologically selfdual, in different orientation)
Dihedral angles
  • between {3} and {3}:   arccos(-sqrt(5)/3) = 138.189685°
  • between {3} and {5}:   arccos(sqrt[(5+2 sqrt(5))/15]) = 37.377368°
Confer
general pyramids:
n/d-py  
related Johnson solids:
pedpy   gyepip   mibdi   teddi   aud   mabaud   pabaud   taud  
uniform relative:
ike  
External
links
wikipedia   mathworld   quickfur

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


Incidence matrix according to Dynkin symbol

ox5oo&#x   → height = sqrt((5-sqrt(5))/10) = 0.525731
(pt || {5})

tip  o. o.    | 1 * | 4 0 | 4 0
base .o .o    | * 5 | 1 2 | 2 1
--------------+-----+-----+----
lace oo5oo&#x | 1 1 | 5 * | 2 0
base .x ..    | 0 2 | * 5 | 1 1
--------------+-----+-----+----
coat ox ..&#x | 1 2 | 2 1 | 5 *
base .x5.o    | 0 5 | 0 5 | * 1

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