Inspired by my first "Inclusions" model, it is in fact very similar to a Sierpinski pyramid (somewhere between level 4 and 5).
Instead of being made by removing matter from a solid tetrahedron, it is made by adding edges to a wireframed tetrahedron.
Thus is is more 3D print friendly (no small sections supporting weight).
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This one has its larger edges measuring 6 cm.
A larger version
is also available.