An extended twisted square pyramid is a Johnson body (J10) in geometry.
As the name indicates, one can construct an extended twisted square pyramid by extending and rotating a square pyramid (J1). This is done by rotating the ground plane 45 ° and connecting the vertices of this base to the vertices of the base of the square pyramid. This results in 8 (equilateral) triangles.
The 92 Johnson bodies were nominated and described by Norman Johnson in 1966. Externe link
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