Acronym etepy
Name elongated tetrahedral pyramid
General of army (is itself convex)
Colonel of regiment (is itself locally convex)
Dihedral angles
(at margins)
  • at {3} between tet and trip (equatorial):   arccos[-sqrt(15)/4] = 165.522488°
  • at {3} between tet and trip (bottom):   90°
  • at {3} between tet and tet:   arccos(1/4) = 75.522488°
  • at {4} between trip and trip:   arccos(1/3) = 70.528779°
Face vector 9, 20, 20, 9
Confer
uniform relative:
pen   tepe  
related CRFs:
etedpy  
general polytopal classes:
bistratic lace towers  

Incidence matrix according to Dynkin symbol

oxx3ooo3ooo&#xt   → pyramidal height = sqrt(5/8) = 0.790569
                     prismatic height = 1
(pt || pseudo tet || tet)

o..3o..3o..    | 1 * * ♦ 4 0 0 0 | 6 0 0 0 | 4 0 0
.o.3.o.3.o.    | * 4 * | 1 3 1 0 | 3 3 3 0 | 3 3 0
..o3..o3..o    | * * 4 | 0 0 1 3 | 0 0 3 3 | 0 3 1
---------------+-------+---------+---------+------
oo.3oo.3oo.&#x | 1 1 0 | 4 * * * | 3 0 0 0 | 3 0 0
.x. ... ...    | 0 2 0 | * 6 * * | 1 2 1 0 | 2 2 0
.oo3.oo3.oo&#x | 0 1 1 | * * 4 * | 0 0 3 0 | 0 3 0
..x ... ...    | 0 0 2 | * * * 6 | 0 0 1 2 | 0 2 1
---------------+-------+---------+---------+------
ox. ... ...&#x | 1 2 0 | 2 1 0 0 | 6 * * * | 2 0 0
.x.3.o. ...    | 0 3 0 | 0 3 0 0 | * 4 * * | 1 1 0
.xx ... ...&#x | 0 2 2 | 0 1 2 1 | * * 6 * | 0 2 0
..x3..o ...    | 0 0 3 | 0 0 0 3 | * * * 4 | 0 1 1
---------------+-------+---------+---------+------
ox.3oo. ...&#x ♦ 1 3 0 | 3 3 0 0 | 3 1 0 0 | 4 * *
.xx3.oo ...&#x ♦ 0 3 3 | 0 3 3 3 | 0 1 3 1 | * 4 *
..x3..o3..o&#x ♦ 0 0 4 | 0 0 0 6 | 0 0 0 4 | * * 1

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