tetra 4 , dual 8 ( double 4 ) , octa 8
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https://www.cosmic-core.org/free/article-46-geometry-platonic-solids-part-7-the-star-tetrahedron/
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2 equally sized dual tetrahedrons in star tetrahedron , inner octahedron , spheres
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tetra 4 , dual 8 ( double 4 ) , octa 8
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