Assertion: tetrahedron | /r/HasProperty | replaced in next stage
Facets:
value: by four tetrahedra
type: OTHER
Source sentences:
text: The starting shape (initiator) for the Sierpinski tetrahedron is a tetrahedron, and it grows according to a rule (generator) whereby each tetrahedron is replaced in the next stage by four tetrahedra set tip-to-tip.