I made both of these while playing around with Stella 4d: Polyhedron Navigator, a program you can try out for free at http://www.software3d.com/Stella.php.
Two Non-convex Polyhedra with Cuboctahedral Symmetry
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Daily Archives: 16 January 2019
A Polyhedron with Isosceles Trapezoids and Regular Pentagons as Faces
I created this using Stella 4d, which you can try for free at http://www.software3d.com/Stella.php.
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